RAMALLAH, West Bank: Palestinian prime minister Salam Fayyad expressed shock at the death of a Palestinian in an Israeli jail Saturday and called for full details of what happened.

Fayyad "expresses his deep sorrow and shock over the martyrdom of prisoner Arafat Jaradat in Israeli occupation prisons," said the statement from his office.

He "affirms the need to promptly disclose the true reasons that led to his martyrdom," it added.

Earlier, Israel Prisons Service spokeswoman Sivan Weizman said Jaradat, a 30-year-old father of two from the West Bank city of Hebron, died suddenly at Megiddo detention centre in northern Israel.

"It was probably a cardiac arrest. I don't have additional details at the moment," Weizman said.

Issa Qaraqaa, the Palestinian minister in charge of prisoner affairs, told AFP that Jaradat had been arrested just a few days earlier.

"He was killed during the investigation," Qaraqaa added.

"We demand the creation of an international commission of inquiry to probe the circumstances of his death."

Israel's Shin Bet internal intelligence service said Jaradat had been arrested on Monday for his involvement in a stone-throwing incident in November during which an Israeli had been wounded.

He was taken ill just before his death, Shin Bet said in a statement.

"After lunch, as he was resting in Megiddo prison, Arafat Jaradat was taken ill. Medics were called to treat him but they were unable to save his life," it added.

Clashes broke out in Hebron between Palestinian youths and Israeli security forces after news of Jaradat's death, witnesses and security sources said.

Relations between Israel and the Palestinian territories are already particularly tense because of protests this month in solidarity with four other prisoners detained by Israel who are on hunger strike.

The Ramallah-based Prisoners' Club announced that another seven prisoners have joined the protest action, although there was no immediate confirmation from the prisons service.