The sound of several blasts could be heard booming through the city in Reuters footage as flashes illuminated the skyline.
Four days of cross-border fighting showed no sign of abating, and Israeli Prime Minister Benjamin Netanyahu said the campaign "will take more time". Israeli officials said Gaza's ruling Hamas group must be dealt a strong deterring blow before any ceasefire.
At least 103 people have been killed in Gaza, including 27 children, over the past four days, Palestinian medical officials said. On Thursday (May 13) alone, 49 Palestinians were killed in the enclave, the highest single-day figure since Monday (May 10).
Seven people have been killed in Israel: a soldier patrolling the Gaza border, five Israeli civilians, including two children, and an Indian worker, Israeli authorities said.