GAZA CITY, Gaza Strip (AP) -- A rocket-propelled grenade hit the home of Prime Minister Ismail Haniyeh of Hamas on Tuesday, in what Hamas said was an attempted assassination. The house was damaged, but Haniyeh and his family were not harmed.

The attack came during the bloodiest 24-hour period yet in latest round of Hamas-Fatah fighting, which erupted again in May, after several weeks of lull. Seventeen people were killed Monday and early Tuesday, including several in street executions, as hospitals turned into battle grounds.

Both Hamas and Fatah, on Web sites and in text messages to activists, called for the execution of the other side's military and political leaders.

Haniyeh's house in the Shati refugee camp on the outskirts Gaza City was damaged by the RPG, but the prime minister and his family were not hurt, said his son, Abdel Salam.

A Hamas Web site described the incident as an assassination attempt. Hamas spokesman Fawzi Barhoum accused Fatah of targeting Palestinian institutions to undermine Hamas rule. "They crossed all the red lines," he said.

The latest fighting disrupted final exams for university and high school students. The three universities called off final exams set for Tuesday. High schools were trying to move test centers to areas out of the range of fire, said Mohammed Abu Shkeir, the deputy minister of education.

Nabil Abu Rdeneh, an aide to Palestinian President Mahmoud Abbas of Fatah, said no end was in sight. "You can see for yourself there's no taste for a cease-fire right now," he told The Associated Press by telephone.

The frustrated head of the Egyptian security delegation, Maj. Gen. Burhan Hamad, who has been trying to negotiate a truce, told Palestinian TV he would call the people out onto the streets to protest if the two rivals do not agree to stand down.

Fatah gunmen stormed the house of a Hamas lawmaker and burned it to the ground.

In another confrontation, the Hamas-controlled Shifa Hospital came under fire from the Fatah-allied Bakr clan, after two of its members were killed in clashes with Hamas. Bakr gunmen fired mortars and rocket-propelled grenades, security officials said, drawing Hamas fire from within the hospital.

The latest deaths brought the number of Palestinians killed since the latest round of infighting erupted in May to more than 80.

Mohammed Madhoun, an aide to Haniyeh, said the building did not appear to have been deliberately targeted. Instead, he said it was caught in the crossfire between rival Fatah and Hamas forces perched on the roofs of nearby buildings. "The ministers are gone and the shooting is indiscriminate," he said.

Hamas and Fatah have been locked in a violent power struggle since Hamas defeated Fatah in January 2006 legislative elections, ending four decades of Fatah rule.

Hamas brought Fatah into its government in March in an effort to quell the internal strife, but the fighting reignited in mid-May over an unresolved dispute over who controls the powerful security forces.