GAZA, Feb 7: Israeli troops backed by tanks, helicopter gunships and warplanes killed six Palestinian gunmen and a schoolteacher in a raid in the Hamas-ruled Gaza Strip on Thursday, militant groups and hospital officials said.

Israel has stepped up military action against Hamas since it claimed responsibility for a Palestinian suicide bombing on Monday, the first such attack by the Islamist faction inside the Jewish state since 2004.

Residents said tanks and heavy bulldozers penetrated the border fence near the northern town of Jabalya. Israeli forces also struck in nearby Beit Hanoun, a border community often used by Palestinian militants to fire rockets into Israel.

Hamas, the ruling Islamist group, said five of its gunmen were killed fighting the Israeli troops. Another gunman, from Islamic Jihad, also died in the clashes, it said.

An Israeli missile hit a school in Beit Hanoun, killing a teacher and wounding three pupils, hospital officials said.

Two of the wounded were initially identified as fellow staff members but the Education Ministry later said all three were pupils aged 16.

“What was the fault of a teacher, an emissary on a sacred mission?” the ministry said in a statement deploring the attack.

An Israeli military spokeswoman said troops had fired on a Palestinian rocket crew spotted inside Beit Hanoun.

“We certainly did not target a school,” she said. An investigation is under way to determine whether the building might have been hit by a stray missile.

The military spokeswoman confirmed there had been an incursion in Jabalya and said forces withdrew after a few hours.

ROCKET FIRE: In the West Bank city of Ramallah, the executive committee of the Palestine Liberation Organisation called on Israel to stop “operations of killing and destruction ... including aggression against houses and schools”.