JERUSALEM (AP) — Israel dramatically escalated its aerial assault targetting hundreds of Hamas sites in the Gaza Strip yesterday as Palestinians reported the strikes also hit a home and a beachside café, raising the total number of people killed in this week’s offensive to at least 85. Israel’s missile defence system also once again intercepted rockets fired by Gaza militants at the country’s two largest cities, Jerusalem and Tel Aviv.

The Israeli military said it had struck a total of some 500 targets throughout the day, focusing on underground tunnel networks and rocket launching sites. In all, the military said it has hit some 860 sites since the operation started Tuesday.

Gaza militants fired more than 140 rockets at major Israeli residential areas yesterday, Israel’s military said. Rockets fired at southern Israel damaged homes, infrastructure and spread panic. Israelis rushed to bomb shelters as sirens wailed in major cities. About five million Israelis are in range of the Palestinian rocket attacks.

Israel has mobilised 20,000 reservists for a possible ground operation into Gaza, but for the time remains focused on maximising its air campaign, said Lt Col Peter Lerner, a military spokesman. A ground invasion could lead to heavier civilian casualties on the Palestinian side and put Israeli ground forces in danger.

Neither side is showing any sign of halting their heaviest fighting since an eight-day battle in late 2012. Israel says that Hamas must cease rocket fire from Gaza for Israel to consider a truce. Militants have fired hundreds of rockets, striking across the length of Israel and disrupting life across the country.

“The ground option needs to be the last option and only if it is absolutely necessary. It is a carefully designed plan of action,” Lerner said.

No Israelis have been seriously harmed as the “Iron Dome” defence system has intercepted at least 70 of the projectiles destined for major cities. The system is designed to intercept rockets headed toward populated areas, while allowing others to fall in open areas.

The limitations of the Iron Dome were seen late yesterday when a heavy barrage of Palestinian rockets hit the major southern city of Beersheba and other areas, severely damaging homes.

Palestinian medical officials said one strike early yesterday struck a home in the southern Gaza city of Khan Younis, killing eight members of the Al Haj family.

An earlier strike killed eight people who were at a Gaza beach cafe watching the World Cup semi-final match between Argentina and the Netherlands, Mahmoud Sawali said, adding at least two of his brothers were among the dead.