Israel launched a massive manhunt in the country’s north and the West Bank early Monday after six Palestinian prisoners tunneled out of their cell and escaped overnight from a high-security facility in an extremely rare breakout.

Four of the six fugitives were in jail for life in connection with deadly attacks against Israelis; the fifth – a notorious commander in Fatah’s Al-Aqsa Martyrs Brigade terror group, Zakaria Zubeidi – was in prison while on trial for two dozen crimes, including attempted murder. Another was held in administrative detention. All six were considered highly dangerous.

The escape marks an embarrassing security breach just ahead of Rosh Hashanah. The prisoners appear to have gone into hiding and there was no indication Israeli authorities view them as an immediate threat.

Palestinians consider prisoners held by Israel to be heroes of their national cause, and many celebrated the escape on social media. Efforts to capture the escapees will likely draw attention to the Palestinian Authority’s security coordination with Israel, which is deeply unpopular among Palestinians. There was no immediate comment from the PA, but President Mahmoud Abbas’ Fatah party praised the escape.

Israeli officials said they have erected roadblocks and are conducting patrols in the area. Israel’s Army Radio said 400 prisoners are being moved as a protective measure against any additional escape attempts. The radio said the prisoners escaped through a tunnel from the Gilboa prison, just north of the West Bank, which is supposed to be one of Israel’s most secure facilities.

A photo released by the prison service showed a narrow hole in the floor of a cell, and Israeli security forces could be seen examining a similar hole on a stretch of gravel just outside the walls of the prison.

Israel’s prime minister, Naftali Bennett, called it a “grave incident” that required maximum effort by Israel’s various security branches.

He said he was receiving constant updates on the prison break. There were no instructions for people to alter their routines.

Police commander Shimon Ben Shabo said officials have reinforced emergency response call centers in the area to respond to any reports about the prisoners and there are “forces available to arrive at any location.”

The escapees were believed to have been headed for Jenin, about a 25 kilometer (15-mile) drive away, where the internationally recognized PA wields little control and where militants in recent weeks have openly clashed with Israeli forces. Israeli helicopters were seen flying over Jenin on Monday morning.

Palestinian terror groups swiftly praised the breakout.

“This is a great heroic act, which will cause a severe shock to the Israeli security system and will constitute a severe blow to the army and the entire system in Israel,” said Daoud Shehab, a spokesman for Islamic Jihad.

Hamas spokesman Fawzi Barhoum cast the escape similarly, saying it shows “that the struggle for freedom with the occupier is continuous and extended, inside prisons. and outside to extract this right.”

Even Abbas’ Fatah party praised the escape, with an official Twitter account posting a picture of Zubeidi and hailing what it called the “freedom tunnel.”

The escape poses a dilemma for Abbas, who met with Israeli Defense Minister Benny Gantz a week ago in the first high-level meeting between the two sides in years. Abbas has said he hopes to revive the peace process after more than a decade-long hiatus under former Israeli Prime Minister Benjamin Netanyahu.

But Abbas’ PA is deeply unpopular. He canceled the first elections in 15 years in April when it appeared his Fatah party would suffer an embarrassing defeat. The Palestinian Authority was largely sidelined during the Gaza war in May, and it has cracked down on a wave of protests following the death of an activist in PA custody that month.

PA security forces coordinate with Israel to target Hamas and other militants that both view as a threat. But any effort to help Israel re-arrest the escaped prisoners risks further undermining the PA in the eyes of Palestinians.

(AP)