Jerusalem - Israel has called on the Palestinian Authority to rein in unrest as militants vowed revenge over the death of a prisoner whom the Palestinians allege died under Israeli torture.
Thousands thronged the West Bank village of Sair on Monday for the funeral of Arafat Jaradat, a 30-year-old father of two and member of the Al-Aqsa Martyrs Brigades after his death at the weekend.
Masked militants fired assault rifles into the air and angry mourners waved Fatah banners and Palestinian flags while Israeli forces stayed away.
Armed and masked Palestinian militants have not been seen in the West Bank since the last intifada, or uprising, which broke out in 2000 and raged for five years.
"This horrific crime will not go unpunished and we promise the Zionist occupation that we will respond to this crime," said a statement from militants of the Al-Aqsa Martyrs Brigades, the armed wing of Palestinian president Mahmoud Abbas's Fatah movement.
Israel called for calm, following a similar plea the previous day, and the United States also urged restraint.
"Israel expects the Palestinian Authority to act responsibly to prevent incitement and violence which will only exacerbate the situation," Mark Regev, spokesperson for Prime Minister Benjamin Netanyahu said.
"Ultimately, not violence but peace talks are what is needed," he added.
Abbas had earlier accused Israel of trying to sow "chaos" in the occupied West Bank, but said his people would not be provoked into violence.
No incidents were reported in Sair but an Israeli military spokesman said there were "scattered protests" in the West Bank.
Around 500 Palestinian youths clashed with Israeli soldiers outside the Ofer military prison near Ramallah, where several hundred Palestinian prisoners are held.
Israeli troops opened fire and used tear gas against the protesters, witnesses said, adding that army snipers were deployed on rooftops of neighbouring buildings.
Palestinian medics said 26 protesters were injured by rubber bullets while seven others were hit by live fire and moderately wounded. An army spokesperson said six Palestinians were hurt by rubber bullets.
Clashes also broke out in Hebron and near Aida refugee camp where a teenager was shot and seriously wounded by Israeli troops, the medics said.
The Palestinian, identified as 15-year-old Odai Sarhan, was transferred to Hadassa hospital in Jerusalem while two others, also hit by live fire in the clashes near Aida camp, were taken to a hospital in nearby Bethlehem.
Protests demanding the release of Palestinian prisoners from Israeli jails and in solidarity with several hunger strikers have rocked the West Bank over the past weeks.
US State Department deputy acting spokesperson Patrick Ventrell said on Monday: "We're sending a clear message to both sides here in terms of restraint."
Noting that Israel was already investigating the death, Ventrell added: "We expect all parties to consider the results of the autopsy calmly and without inflammatory rhetoric."
Call for restraint
Israeli prison authorities say Jaradat appeared to have died of a heart attack and that fractured ribs discovered in the autopsy could have been caused by efforts to resuscitate him.
The UN special co-ordinator for the Middle East peace process, Robert Serry, called for "an independent and transparent investigation" into the death.
Serry warned of "a real risk of destabilisation" and called on all parties to show restraint "to prevent further violence".
The Palestinians have also called for an independent investigation in a letter to the UN Security Council. The letter said that Jaradat, who died at the weekend, may have been tortured.
The letter, sent by Palestinian UN ambassador Riyad Mansour to the Security Council, said Jaradat had six broken bones in his neck, spine, arms and legs, along with other injuries.
Israeli media have linked the unrest and concerns over a possible escalation to next month's visit by US President Barack Obama to the Jewish state and the Palestinian territories.