The Hamas movement closed the Erez crossing between the blockaded Gaza Strip and Israel Sunday in response to the mysterious killing of one of the group's leaders. Interior Ministry spokesman Iyad al-Bozum said it was part of security measures put in place after Mazen Faqha, a leader of the group's military wing, was shot dead by unidentified gunmen on Friday. The rare measure reflects Hamas' shock after one of its senior militants, Faqha, was found shot dead at the entrance of his Gaza City house late Friday. Hamas, the Islamic militant group that rules Gaza, said Faqha was shot four times in the head with a silenced gun and blamed Israel for "assassinating" him.

Israel Radio reported that Israeli forces near Gaza were put on high alert on Saturday in anticipation of Hamas retaliating to the killing. Hamas's military wing, the Al-Qassam Brigades, said in a statement that it held Israel responsible and that "the occupation will pay a heavy price for this crime."

Palestinian political analyst Talal Awkal told Anadolu Agency that a potential reaction from Hamas could be unconventional and take time to prepare. Faqha was released in 2011 as part of a prisoner swap that involved Israel freeing 1,027 Palestinian prisoners in exchange for the release of Israeli soldier Gilad Shalit, who was captured by Hamas in 2006. Israel held Faqha responsible for directing attacks against Israelis from the occupied West Bank, but he was deported to Gaza after being released from prison.