May 18 (UPI) -- Israel reported Sunday it found the body of Hamas ' de facto leader, Muhammad Sinwar, in a tunnel in Khan Younis after he was killed in a series of airstrikes last week. At least 100 people have been killed in the latest series of airstrikes , and Sinwar's body was found as Hamas has offered to release nine hostages in exchange for a 60-day military stand down in an effort to slow down the fighting in the ongoing war between Israel and Hamas. Sinwar was the younger brother of