GAZA CITY, Gaza Strip - Israeli tank fire wounded 11 people, including at least six militants, in the Gaza Strip on Wednesday following an attack on an Israeli patrol, the military and Palestinian officials said.

The Israeli military said its tanks opened fire after the militants detonated a bomb targeting the Israeli patrol near the border and then fired mortars at the soldiers.

Gaza health officials say two of the wounded militants were in serious condition. Both Islamic Jihad and Hamas militants say they fired mortars at the troops. No Israeli soldiers were hurt.

Israel and Hamas have largely observed an unofficial cease-fire since an Israeli military offensive in Gaza two years ago. But clashes sporadically flare up along the volatile border as Gaza militants fire rockets and mortars into Israel, drawing military reprisals.

Wednesday's incident marked the first time in weeks the clashes have produced casualties.

Meanwhile, a large explosion in the southern Gaza Strip killed a 10-year-old girl and wounded two others. Gaza's Hamas rulers said they were investigating the cause of the blast.

Internal explosions are common in Gaza. They often take place in the homes of militants where explosives and other armaments detonate prematurely.