At least 75 people, including many children, have been killed in the Gaza Strip in two days of Israeli air raids, as Israel’s army mobilised on the border for a possible ground invasion.

The Palestinian Ministry of Health said 550 people had been wounded since Israel launched its campaign in Gaza this week, which it said targeted Palestinians firing rockets into its territory.

The Israeli authorities say more than 200 rockets have been fired into Israel from Gaza since Monday, with some reaching as far as Tel Aviv.

At least 550 sites have been hit by Israeli jets, including Gaza City, Beit Hanoun and Khan Younis.

An Israeli air strike killed seven Palestinian civilians on Thursday, including five children, in the largest death toll from a single attack since the start of the three-day offensive, the Palestinian Ministry of Health said.

Residents and medical officials said an Israeli air strike bombed at least two houses in a densely populated area near Khan Younis while residents were asleep, the Reuters news agency reported.

Bodies were pulled out of rubble from three or four homes including neighbouring structures. Another 16 people
were also wounded in the attack, the ministry said.

Israeli tanks continued to patrol the border of Gaza, after Israel’s cabinet mobilised 40,000 reservists.

Al Jazeera’s John Hendren, reporting from Gaza City, said people are concerned that the next step is a ground invasion.

“Israel says it has thousands more targets it is willing to strike, which is hard to believe when you’re in Gaza City. People are worried about more air strikes and a ground war.”