JERUSALEM, Aug 1 (Reuters ) - Israeli aircraft bombed a smuggling tunnel and a militant training camp in the Gaza Strip on Sunday after a rocket was fired into Israel from the territory, the Israeli army and militants said.

The air strike caused damage but no casualties were reported. The rocket that militants launched on Saturday caused heavy damage to Israeli buildings close to the border with the Gaza Strip, the army said. Nobody was hurt.

Jihadist Salafi groups issued a statement claiming the launch. They have repeatedly accused Hamas, which rules Gaza, of preventing them from launching rockets at Israel, and say it sometimes arrests those attempting to do so.

It was the second such instance of Israel responding to rocket fire in less than two days.

On Friday, a rocket fired from Gaza landed in the Mediterranean coastal city of Ashkelon, blowing out windows of an apartment block and damaging parked cars. Israel replied with strikes that killed a Hamas military commander in the Gaza Strip, Hamas said.

The exchanges marked a raising of tensions between Israel and Gaza militants after a period of relative calm. The army said some 110 rockets and mortars have been fired at Israel since the start of 2010.

Israel staged a devastating three-week offensive against Gaza in December 2008 and January 2009 with the stated aim of halting rocket attacks from the territory. (Writing by Ori Lewis; Editing by Mark Trevelyan)