Israel pounded Gaza on Saturday, destroying a tower block that housed news media organisations, while Palestinian rocket salvoes hit Tel Aviv with no sign of an end to almost a week of fighting.
Palestinians say at least 145 people, including 41 children, have been killed in Gaza since the conflict erupted on Monday. Israel has reported 10 dead, including two children.
Israel's military brought down a 12-storey block in Gaza City that housed the US Associated Press and Qatar-based Al Jazeera media operations, as well as other offices and apartments.
Israel gave advance warning of the strike so the building could be evacuated. The Israeli military said later it was a legitimate military target because it contained military assets of Hamas, the Islamist group that runs Gaza.
The strike was condemned by the AP and Al Jazeera. The United States told Israel "that ensuring the safety and security of journalists and independent media is a paramount responsibility," White House Press Secretary Jen Psaki said.
US President Joe Biden later spoke to both Israeli Prime Minister Benjamin Netanyahu and Palestinian President Mahmoud Abbas to urge calm.
The White House said Biden updated Netanyahu on "high-level" contacts with regional partners to restore calm, and raised concerns about the safety of journalists.