Israeli airstrikes have levelled a seven-floor office building and severely damaged a two-storey commercial building with dozens of shops, Gaza police say.
An office of the Hamas-run interior ministry was located in the seven-storey Zourab building in the southern town of Rafah.
Police say seven people were wounded by the bombing of the commercial centre. There were no reports of casualties from the other strike.
The strikes early today came hours after Israel toppled a 12-storey apartment block in Gaza City. Israel says it targeted a Hamas operations room in the tower.
Meanwhile, the Israeli military says five rockets were fired from Syria at the Israeli-annexed Golan Heights, falling in open areas.
Amid signs of further escalation, Egypt has urged both sides to resume indirect cease-fire talks in Cairo.