At least eight people have been killed and 35 more wounded in a shootout at a Jewish school in west Jerusalem.
Agencies quoted witnesses as saying that two armed men entered the yeshiva, or religious school, and opened fire on Thursday.
According to witnesses, the armed men entered a dining hall where about 80 people were gathered, and opened fire.
The school is a well-known centre of Jewish studies linked with those leading the Jewish settler movement in the occupied West Bank.
There has been no claim of responsibility.
Al Jazeera’s Ayman Mohyeldin, reporting from the scene, said that questions will be raised as to how the assailants passed through the many security checks situated in the area.
"There are numerous checkpoints throughout the city," he said.
"The deaths will ultimately raise many questions regarding the apparent lapse in surveillance around the school."
Marwan Bishara, Al Jazeera’s senior political analyst, said that the attack is a major escalation, and points to a premeditated attack from the Palestinian territories.
"The shootout displays a carefully planned operation, and it would be no surprise if the Israeli government uses this as another pretext to launch further assaults on the Palestinian population," Bishara said.
Shmuel Ben Ruby, Jerusalem police spokesman, said: "One or two terrorists infiltrated the Mercaz Harav seminary and opened fire in all directions.
"One terrorist was killed in an exchange of fire, and apparently he had an explosives belt."
In the Gaza Strip, people fired in the air to celebrate the attack, which occurred three days after Israel ended a military offensive in the Hamas-run territory that killed at least 120 people.
(Aljazeera and agencies)