Hamas official Mazen Faqha was assassinated late Friday in the Israeli-blockaded Gaza Strip, the Hamas-run Interior Ministry in Gaza said.
"Faqha was assassinated by unidentified [attackers] in the Tal al-Hawa area," the ministry said.
Shortly after the incident, Ezzedin al-Qassam Brigades, the arned wing of Hamas, confirmed the incident on their website, describing Faqha as was one of their leaders.
Hamas for its part, issued a statement early Saturday and held Israel responsible for Faqha's death.
"Hamas Movement and its brigades hold the Zionist occupation and its agents totally responsible for this awful crime," the statement read.
Faqha was sentenced to nine terms of life imprisonment for directing suicide bombing attacks against Israelis.
He was freed along with more than 1,000 other prisoners as part of an exchange in 2011 that released captive Israeli soldier Gilad Schalit.