Israel Air Force planes struck a tunnel in the northern Gaza Strip early Sunday in response to a Qassam rocket fired by Palestinian militants into the western Negev early Saturday.

Also on Sunday, Army Radio said an IDF unit patrolling Gaza's northern border reported it went under fire. No injuries were reported.

The Israel Defense Forces said the attacked tunnel was was dug from underneath a building located one and a half kilometers away from the security fence.

An Israeli security source said intelligence indicated the tunnel had been dug by several Palestinian factions other than Hamas.

It was intended for use to infiltrate into Israeli territory in order to execute a terrorist attack against Israeli citizens or IDF soldiers, the IDF added.

Hamas described the target of the Israeli air strike as "open ground" but witnesses said it was a building with two rooms and a courtyard, which were ravaged by the attack.

The rocket fired by Palestinian militants hit an open area in the Sdot Negev regional council.

The Palestinian Maan news agency reported on Saturday that the Israel Defense Force fired artillery rounds at gunmen at the central Gaza Strip. No injuries were reported.

The IDF said in response that no such attack took place.

According to the report, the IDF also opened machine-gun fire from vehicles stationed on the border toward nearby central Gaza homes.

The Qassam, fired at around 6 A.M., was one of several military incidents along Israel's boarder with Gaza, coming after months of relative calm.

On Tuesday, Gaza militants fired two mortar shells at the western Negev, which landed near an Israel Defense Forces base.

One soldier was lightly wounded and received medical treatment on site.

The Israel Air force responded later that day with bombing smuggling tunnels in the southern Gaza Strip. Three Palestinians died in the assault

Also, earlier in the month, militants fired mortars at a crossing into Israel just as Palestinian patients were being transferred for treatment.

The IAF responded by attacking smuggling tunnels, with no known casualties on the Palestinian side.

In another recent incident, an IDF patrol opened fire on Palestinian militants on Monday after spotting their approach to the Gaza border fence.

Palestinian sources said three people were wounded in the cross-border fire.

Bombs detonated at Hamas compounds in Gaza Unidentified persons set off bombs at two Hamas security compounds in the Gaza Strip early Sunday, causing no casualties, the Palestinian Islamist group said.

There were no immediate claims of responsibility for the attacks on the Ansar-2 prison and the Gaza residence of Palestinian President Mahmoud Abbas, whose secular Fatah faction was forced out of the territory by Hamas in a 2007 civil war