Palestinian militants in Gaza launched a rocket Tuesday that fell near the Israeli city of Ashkelon, Israeli police said, causing no injuries but threatening to upset a recent period of calm.

Israeli Prime Minister Ehud Olmert left the city a short time before the rocket hit.

The rocket landed in an open area south of the city of 120,000, police spokesman Micky Rosenfeld said. The launch came during a lull in fighting between Israel and Hamas militants in Gaza following a round of intense violence that left three Israelis and 120 Palestinians dead, including dozens of civilians.

Dozens of rockets hit Israel every day during the fighting, including many that targeted Ashkelon, the first time the coastal town had been heavily bombarded by Palestinian militants.

Israel pulled its forces out of Gaza last week and militants scaled back their rocket fire. Egypt has been serving as a mediator between Israel and Gaza's Hamas rulers, but both sides have denied there is an official cease-fire in place.

There was no immediate claim of responsibility from Gaza for the rocket fire Tuesday.