The latest deaths bring the number of Palestinian journalists killed in the fighting since Saturday to eight, the Palestinian Press Union said in a statement.

Another union, the Gaza journalists' syndicate, announced earlier "the martyrdom of three journalists in the Gaza Strip in the ongoing Israeli aggression".

The chief of Gaza's Hamas-run government media office, Salameh Maarouf, identified the three as Said al-Taweel, director of Al-Khamisa news agency; press photographer Mohammed Sobboh, and Hisham Nawajhah, a correspondent for a Gaza news agency.

They were killed in a strike while covering the evacuation of a residential building near Gaza City's fishing port, Maarouf said, condemning Israel's "criminal behaviour against journalists".

Members of the press were standing several dozen metres (yards) from the building after a resident received a telephone call from the Israeli army warning of an imminent strike, an AFP correspondent reported.

Witnesses said the Israeli strike hit a different building, closer to where the journalists had been.

Later on Tuesday, the press union said the head of its committee of women journalists, Salam Khalil, was killed along with her husband and children when the family's home in the northern Gaza Strip was hit in a "treacherous" Israeli bombing.

Journalist Asad Shamlakh was killed on Sunday, the media office statement said, adding two cameramen were missing and 10 journalists have been wounded.

Three journalists were killed on Saturday, according to the Palestinian statement and the Committee to Protect Journalists.

The New York-based media rights group said on Monday that Ibrahim Mohammad Lafi, a photographer, Mohammad Jarghoun, a reporter, and Mohammad El-Salhi had been shot dead in different incidents.

"We call on all sides to remember that journalists are civilians and should not be targeted," Sherif Mansour of the Committee to Protect Journalists said in a statement.

"Accurate reporting is critical during times of crisis and the media has a vital role to play in bringing news from Gaza and Israel to the world."