Israeli Prime Minister Benjamin Netanyahu on Tuesday delivered a stern warning to Palestinian militants in the Gaza Strip, saying that Israel would respond with "strength" to incessant rocket fire from the coastal territory.

"Hamas hides among the civilian population and fires from there at our communities," Netanyahu said during a meeting with the mayor of Beersheba, the largest city in the Negev desert, whose residents have been targeted by dozens of rockets in recent years.

"We will respond in strength to every place from which we are fired at," the premier added, according to a statement.

The remarks came after more than 20 rockets were fired at Israeli communities bordering Gaza overnight Sunday and throughout Monday, ending an informal truce that went into effect last week amid the worst cross-border violence in months.

The Israeli Air Force launched several retaliatory strikes against rocket-launching crews and other militant sites, the army said.

There were no reports of casualties on either side.

On Monday, Izz al-Din al-Qassam, the military wing of Hamas, released video footage of rockets fired in succession from a crowded Gaza neighborhood.

"Our response to the aggression of the Zionist enemy will be harsh and painful," said Hamas spokesman Fauzi Barhum.

Also Monday, Israeli aircraft scattered leaflets over southern Gaza, urging Palestinians to remain at least 300 meters from the border fence or risk getting shot.