The Palestinian Islamic group Hamas vowed to avenge the death of an activist killed in a helicopter strike and Palestinian gunmen shot dead an Israeli settler as an upsurge of violence in the region showed no sign of abating. "Our mujahedeen will avenge our martyr as soon as possible to ensure that the Zionists pay the price," said a statement from Hamas's armed wing, the Ezzedin al-Qassam Brigades. Hamdi Kalakh, 24, was killed in the air strike while riding his donkey cart near the southern town of Khan Yunis late Thursday, in the fourth attack on Hamas militants in a week. Three bystanders were also wounded. His killing appeared to be Israeli retaliation for a Qassam rocket being fired on the outskirts of the major port city of Ashkelon, the first time an improvised rocket fired from the Gaza Strip had reached so far into Israel. Hamas and Islamic Jihad formally ended a seven-week ceasefire last week after Hamas co-founder Ismail Abu Shanab was killed in a retaliatory Israeli air strike in Gaza City. A Jewish settler was killed and his wife seriously wounded by Palestinian gunmen Friday as they were driving north of the West Bank city of Ramallah. The attack was claimed in a phone call to AFP by the Al-Aqsa Martyrs' Brigades, an armed offshoot of Palestinian leader Yasser Arafat's Fatah movement. **PHOTO CAPTION*** Zionist soldiers terrorizing Palestinian Muslims. (AFP/Jaafar Ashtiyeh)