JERUSALEM — Israeli police armed with stun grenades and tear gas clashed with rock-throwing Palestinian youths who barricaded themselves inside Jerusalem’s al-Aqsa mosque on Tuesday, police and witnesses said. The violence had been ongoing for three days.

Masked Palestinians hurled flares at the security forces, who said they were trying to secure the plaza outside Islam’s third holiest shrine to stop what they said was a Palestinian attempt to disrupt visits to the compound on Jewish New Year.

The United States and U.N. Secretary-General Ban Ki-moon both voiced concern about the violence at the site, revered by Muslims as the Noble Sanctuary and by Jews as the Temple Mount. 

King Abdullah from neighboring Jordan said the Israeli actions were provocative and could imperil ties between the countries, state media reported on Tuesday, and Palestinian President Mahmoud Abbas condemned Israel’s actions.

Jordan’s Hashemite dynasty derives part of its legitimacy from its traditional custodianship of the holy site. “If this continues to happen … Jordan will have no choice but to take action,” King Abdullah, whose father King Hussein signed a peace treaty with Israel in 1994, was quoted as saying.

Palestinians fear that the increasing visits by Jewish groups to the site, captured by Israeli forces when they seized east Jerusalem and the rest of the West Bank in a 1967 war, are eroding Muslim religious control there.

Palestinian Presidency spokesperson Nabil Abu Rdeinah said Abbas and King Abdullah had discussed the events by phone. “(Israel’s) religious war will drag the region into endless fighting,” Abu Rdeinah said in a statement.

Israeli Prime Minister Benjamin Netanyahu was due to hold an emergency ministerial meeting late on Tuesday, called after an Israeli motorist died in a crash police said was caused by suspected stone-throwing.

Twenty-six Palestinians were injured on Tuesday, none of them seriously, the director of the Palestinian Red Crescent emergency unit, Amin Abu Ghazaleh, said.

Jewish ultra-nationalists have been pushing the Israeli government to allow Jewish prayer on the compound outside al-Aqsa, which stands above Judaism’s Western Wall.

Such worship, certain to stir Muslim anger, has been banned on the plaza by Israel since 1967 and Netanyahu has said he would not allow any change to the religious status quo.

Israel regards all of Jerusalem as its indivisible and eternal capital, a claim not recognized internationally.