JERUSALEM – Yahya Sinwar, Hamas’ top leader in Gaza, his younger brother, Muhammed, and two other senior military commanders of the Iranian-backed Islamist terror group – Rafa’a Salameh and Mohammad Deif – are considered to be the worst killers from the southern Gazan city of Khan Younis. All are now the most wanted terrorists by Israel.As the IDF gears up for what could be its fiercest battle yet against Hamas, the army dropped leaflets over Gaza’s second most populous city on Thursday, calling on residents of the Hamas stronghold to share any information about the whereabouts of the four men and offering a substantial financial reward – some $1 million in total – for anyone brave enough to come forward.All four terrorists were born and raised in Khan Younis, a city about two miles east of the Mediterranean Sea, and Sinwar, who already has the nickname “the Butcher of Khan Younis,” for his violent and cruel torture methods against his enemies, both Israeli and Palestinian, is widely seen as the mastermind of the massacre of Israeli civilians carried out by thousands of Hamas terrorists on Oct. 7, sparking the current war. ISRAEL’S HUNT FOR HAMAS TERROR GROUP LEADER YAHYA SINWAR: ‘DEAD MAN WALKING’ Israel recently released flyers in Gaza calling for help tracking down four of its most wanted terrorists. Rewards were offered for information. (Julia Bonavita/Fox News Digital )Israeli political and military leaders have referred to Sinwar as a “dead man walking.”So, who are the four men Israel is willing to dole out a million dollars for?Wanted: Yahya SinwarPosition: Hamas leader in Gaza Bounty: $400,000Yahya Sinwar, who turned 61 at the end of October, was born in the Khan Younis refugee camp when the region was part of Egypt. According to multiple sources, he has always been a militant activist and joined Hamas not long after its founding in 1987. Two years later, he was arrested by Israel for his involvement in the abduction and killing of two Israelis, as well as the torturing and murder of four Palestinians he considered to be collaborators. He was sentenced to life in prison and ended up serving 22 years in an Israeli jail until his release in 2011 as part of a prisoner exchange for the abducted Israeli soldier Gilad Shalit. Yahya Sinwar, center, appears during a ceremony for fighters killed by Israeli airstrikes on May 24,2021 in Gaza City. (Laurent Van der Stockt/Getty Images))During his time in jail, Sinwar became a prominent and influential figure among the other Hamas prisoners and learned to speak fluent Hebrew. He has a deep understanding of Israeli society, those who have met and studied him say, pointing out that he is both charismatic and extreme, with strong ideological and religious beliefs. He is not afraid to die or sacrifice himself for the Palestinian cause and truly believes that he can lead the Palestinian people to destroy Israel. ISRAELI POLICE SAY EXTREME SEXUAL VIOLENCE, RAPE BY HAMAS TERRORISTS WAS SYSTEMATICWanted: Mohammad SinwarPosition: Commander of Hamas’ Southern BrigadeBounty: $300,000 Mohammad Sinwar, Yahya’s younger brother by a few years, joined Hamas’ military wing in the early 1990s and also spent a few years imprisoned for terrorist activities. Upon his release, the younger Sinwar upped his militaristic activities with Hamas, taking part in several deadly terror attacks against Israel in the mid-1990s before becoming commander of the terror group’s Khan Younis Brigade in 2005. In 2006, according to reports, Mohammed Sinwar was involved in a deadly attack against Israeli soldiers on Israel’s border that resulted in the kidnapping of IDF soldier Gilad Shalit. He was then part of the secretive Hamas cell that held Shalit captive in Gaza for more than five years. This image made from undated bodycam video footage taken by a downed Hamas terrorist and released by Israel Defense Forces shows a Hamas terrorist walking around a residential neighborhood at an undisclosed location in southern Israel on Oct. 7. (Israel Defense Forces via AP)While the younger Sinwar is considered to be of lower rank than his leader brother, the two are very close, according to experts. “He is involved in decision-making and was very involved in planning the Oct. 7 attack with him,” Michael Milshtein, head of the Palestinian Studies Forum at the Dayan Center at Tel Aviv University, told Fox News Digital. Wanted: Rafa’a SalamehPosition: Commander of Khan Younis Battalion Bounty: $200,000 Currently, the commander of the Hamas battalion where most of Israel’s fighting is now focused, Milshtein said Rafa’a Salameh was not generally considered a prominent figure and was most likely to have been included on the list because, like the others, he was born and raised in Khan Younis. Milshtein also said putting him in Israeli military crosshairs serves to weaken the enemy. Hamas terrorists on July 20, 2017, in Gaza City. (Chris McGrath/Getty Images)”When all the efforts are focused on Khan Younis and you want to make the enemy weaker, then you put him on the list, that is why he is one of the four,” he said. UN, HUMAN RIGHTS, MEDIA GROUPS RELY ON HAMAS DEATH TOLL IN ‘SYSTEMATIC DECEPTION’: EXPERTWanted: Mohammad DeifPosition: Commander of Hamas military wing Bounty: $100,000 Notably, Mohammad Deif, long considered to be enemy number one for Israel and considered as senior in Hamas as Yahya Sinwar, has a lower bounty than the other three. An undated photo of Mohammad Deif, the mastermind of Hamas suicide bombings. Little is known about the Palestinian who has kept one step ahead of the Israelis. (Reuters)As the top commander of Hamas’ military wing, the Izzedine al-Qassam Brigades, Deif, 58, is also thought to have been involved in planning the brutal Oct. 7 attacks. A master bombmaker, Deif played an instrumental role in developing Hamas’ military capabilities, Israeli military and intelligence officials have said, including building up its rocket arsenal and attack strategy, as well as helping to design the subterranean tunnel system, which snakes for miles below the coastal enclave and which Israel is now trying to eradicate. A former actor, Deif, is a master of disguise and has long eluded the Israelis, even surviving several assassination attempts. It is believed that Deif, who is sometimes referred to as “the cat with nine lives,” has been confined to a wheelchair since an Israeli attack in 2006 during which he also lost an eye and an arm. However, Israel’s arch-enemy keeps a very low profile, rarely making public appearances – the last known photo of him is at least three decades ago.Milshtein, who has studied Hamas’ most elusive warrior for years, told Fox that he is “far more important than Salameh, of course, but someone in Israel tried to make him angry or make a joke out of him by making him worth less.” In the deck of playing cards, Deif, shown as a one-armed mannequin, is king. The IDF recently released a deck of cards showing the most wanted terrorists. “It’s unlikely anyone will call the number on that flyer,” Milshtein told Fox News Digital. “There is a beehive surrounding Sinwar and he is very confident about his position in Gaza and inside Hamas,” said Milshtein, who previously headed the department for Palestinian affairs in the IDF’s military intelligence unit. “I would be very surprised if anyone would betray him or give Israel any important information about his location.” Israeli forces have been engaged in operations in Khan Younis since early December, when a week-long cease-fire with Hamas ended. On Dec. 6, Israeli Prime Minister Benjamin Netanyahu announced that Israeli forces had reached and encircled Sinwar’s home, although Israel’s most wanted terrorist was obviously not home.”His home is not his castle, and he can flee, but it is only a matter of time until we find him,” Netanyahu said in a brief statement. ‘I WILL BE HAUNTED FOREVER’: ISRAEL’S HORRIFIC VIDEO OF HAMAS ATROCITIES LEAVES VIEWERS SHOCKED AND SICKENEDAs well as Sinwar, Israel has said it will seek out and assassinate other members of Hamas’ political and military leadership wherever they are in the world. Last week, IDF soldiers fighting in Gaza were given packs of playing cards, similar to those created for U.S. troops during the Iraq war, depicting the most wanted Hamas terrorists. Yahya Sinwar, shown as a rat hiding in a tunnel, is the ace card. Yahya Sinwar, shown as a rat hiding in a tunnel, is the ace card in the deck given to Israeli soldiers. Despite making clear that these brutal killers are in Israel’s sights, after more than 70 days of fighting – and an estimated 7,000 dead terrorists and thousands more captured – only a handful of Hamas’ top tier have been taken out.Among the top figures killed in fighting so far is Rawhi Mushtaha, a political and strategic leader, considered to be Sinwar’s “twin” and the man said to be most knowledgeable about the Palestinian prisoners Hamas is hoping to exchange for more than 120 Israeli hostages, including women and children, that it brutally kidnapped on Oct. 7 and still holds. In addition, the IDF and Israel’s internal security agency, Shin Bet, on Dec. 5 said several senior Hamas operatives from the military brigades of northern Gaza had been eliminated, including Ahmed Al-Ghandoor. According to the information shared, Al-Ghandoor was part of the military wing’s inner circle and had been responsible for directing and managing all the group’s terror operations in Northern Gaza. An image released by the IDF on Friday, Dec. 15, showing fighting unfolding in the Gaza Strip. (IDF)Another senior member of the Islamist organization’s general military council to be eliminated was Ayman Noufal, who was head of Hamas’ central command. Noufal was killed by an Israeli airstrike early on in the war, Hamas confirmed in a statement. Jonathan Schanzer, the senior vice president for research at the Foundation for Defense of Democracies in Washington, told Fox News Digital that the “most wanted” leaflets dropped by the IDF over Khan Younis were symbolic of what will likely be one of the “toughest battles for Israel in this war.” CLICK HERE TO GET THE FOX NEWS APP ”Hamas used the cease-fire to prepare for this battle,” he said, adding that Sinwar and the others identified as top tier by Israel hail from the place that “could soon be described as Hamas’ last stand.””Israel has other top targets in its sights but the killing or capture of these men might signal a psychological win for the Israelis and even a defeat for the Iran-backed group in Gaza,” Schanzer said.”I don’t believe Gazans will turn them over, but these men have to be feeling the heat even more right now, with their names plastered all over war-torn Gaza.” Ruth Marks Eglash is a veteran journalist based in Jerusalem, Israel. She reports and covers the Middle East and Europe. Originally from the U.K, she has also freelanced for numerous news outlets. Ruth can be followed on Twitter @reglash