JERUSALEM, Aug 5 (Reuters) - Israeli aircraft struck what its military said were rocket launch sites in south Lebanon early on Thursday in response to earlier projectile fire towards Israel from Lebanese territory.

Two rockets launched from Lebanon on Wednesday struck Israel, which responded with artillery fire amid heightened regional tensions over an alleged Iranian attack on an oil tanker in the Gulf last week.

There was no claim of responsibility for the rocket strike, launched from an area of south Lebanon under the sway of Iranian-backed Hezbollah guerrillas. There were no casualties.

In a further response to the rocket fire, the Israeli military said on Thursday that its "fighter jets struck the launch sites and infrastructure used for terror in Lebanon from which the rockets were launched."

An additional target in the area that was a source of rocket fire in the past was also struck, the military said.

Hezbollah's Al-Manar TV said that Israeli warplanes had carried out two raids in the outskirts of the Lebanese town of Mahmudiya, about 12 km (7.5 miles) from the Israeli border.

The border has been mostly quiet since Israel fought a 2006 war against Hezbollah, which has advanced rockets.

But small Palestinian factions in Lebanon have fired sporadically on Israel in the past, including two rockets launched towards Israel in July.