JERUSALEM — Israel dramatically escalated its aerial assault in Gaza Thursday hitting hundreds of Hamas targets, as Palestinians reported 16 people killed in strikes that hit a home and a beachside cafe and Israel’s missile defense system once again intercepted rockets fired by militants at the country’s heartland.

Military spokesman Lt. Col. Peter Lerner said Israel struck more than 320 Hamas targets overnight, focusing on underground tunnel networks and rocket launching sites. That brought the total number of targets hit to 750 in three days of the massive offensive that has killed at least 80 Palestinians.

Lerner said Israel has already mobilized 20,000 reservists for a possible ground operation into Gaza, but for the time being Israel remained focused on maximizing its air campaign. A ground invasion could lead to heavy civilian casualties on the Palestinian side while putting 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. No one has been seriously harmed as the “Iron Dome” defense system has intercepted at least 70 of the projectiles destined for major population centers.

“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.

The Israeli security Cabinet was meeting to discuss its next moves.

Defense Minister Moshe Yaalon said the operation was going according to plan, with Israel targeting various Hamas interests.