JERUSALEM - Israel re-opened the Al-Aqsa mosque after Palestinian officials called for "immediate non-violent strikes" in Jerusalem to oppose the Israeli closure of the holy site on Friday afternoon.

For several hours all entry into and out of the mosque, which is Islam's third holiest site, was prevented by Israeli officers.

The compound was reopened in the early evening, with worshippers flooding in to pray, according to an AFP photographer.

Calls for protests came after Israeli police fired upon Palestinian worshippers inside the Al-Aqsa compound after afternoon Friday prayers, sparking mass panic and hysteria inside the holy site.

"After being in touch with the religious leadership, they called for non-violent action/protest and prayed in front of lions gate until they open the Al-Aqsa mosque," Omar Alkeswani, manager of Al-Aqsa mosque complex said in a statement.

Images posted online showed worshippers praying outside in the Old City of Jerusalem to oppose the closure.

Israeli forces fired tear gas and sound grenades at unarmed Palestinians. Eyewitnesses told Middle East Eye that Israeli police had barricaded entrances to the mosque, preventing people from entering the historic building.

It remains unclear why Israeli forces had begun to fire upon worshippers.

Sheikh Ekrem Sabri, an imam of the mosque, told MEE that Israeli forces had given no warning.

"The occupation forces attacked worshippers suddenly without warning after Friday prayers were finished inside Al-Aqsa," said Sabri.

"The attack caught people by surprise."

Sabri also added that guards belonging to the Islamic Waqf, which runs affairs inside the compound, were also attacked by Israeli police who moved in to close down the area.

Mohammed Sadiq, a Jerusalem-based journalist, said that Israeli forces had attacked medical teams attempting to help people injured from the tear gas.

Palestinian media reported tens of worshippers were injured.

An Israeli police spokesman said firecrackers and stones were lobbed at police "for an unknown reason". Police were clearing the compound in response, he said.

This latest escalation comes a year after Palestinians successfully stopped Israel setting up cameras and metal barriers at the entrances of the compound - which Jews refer to as the Temple Mount - in Jerusalem's Old City.

The metal barriers sparked mass protests at the time, leading to four Palestinians being killed, while dozens were injured by Israeli forces.