An Israeli airstrike on a school housing displaced Palestinian families killed at least 12 people, including children, on Wednesday.
"At least 12 people were killed, including several children and women, in a strike by an Israeli drone this morning on a tent for displaced persons" near Khan Younis, the agency's spokesman Mahmud Bassal told AFP, adding that four more people had been killed in other strikes.
Residents said Israeli military escalated airstrikes and tank shelling on parts of Khan Younis, a day after it dropped leaflets warning residents to leave their homes and head west, claiming its forces would be "fighting Hamas and other militants" in the areas.
At the same time, aid centres in hunger-wracked Gaza will temporarily close on Wednesday, a controversial US and Israeli-backed agency said, with the Israeli army warning roads leading to distribution stations "are considered combat zones".
Twenty-seven people were killed in southern Gaza on Tuesday when Israeli troops opened fire near one of the centres operated by the Gaza Humanitarian Foundation.