KARAK, Jordan: Jordanian special forces killed four gunmen late Sunday evening, ending a standoff at a Crusader castle where the armed men holed up after a series of deadly attacks, and seizing an arms cache.

The gunmen had earlier ambushed Jordanian police at the fortress popular with tourists, killing seven officers, two local civilians and a woman visiting from Canada, officials said.

At least 27 people were wounded in one of the bloodiest attacks in Jordan in recent memory.

The standoff between Jordanian special forces and armed men holed up inside the castle ended well after nightfall, several hours after the first shooting. Government officials declined comment on local news reports that the attackers had taken hostages who were later freed.

The shootings were the latest in a series of attacks that have challenged the pro-Western kingdom’s claim to be an oasis of calm in a region threatened by Islamic extremists. The killing of the Canadian tourist could further hurt Jordan’s embattled tourism sector, which has declined sharply since Daesh (ISIS) seized large parts of neighboring Syria and Iraq two years ago.

There was no immediate claim of responsibility for the attacks in and near the town of Karak, 140 kilometers south of the capital, Amman.

A former government minister from Karak city, Sameeh Maaytah, said there were signs Islamist militants may have been behind the attack but the government has so far steered away from saying this. “This was a group that was plotting certain operations inside Jordan,” Maaytah told pan-Arab news channel Al-Hadath.

Video footage on social media showed security forces taking groups of young Asian tourists up the castle’s steep steps to its main entrance as gunshots were heard overhead.

The chain of events began when a police patrol received reports of a house fire in the town of Qatraneh in the Karak district, a statement by Jordan’s Public Security Directorate said. The officers responding to the call came under fire from inside the house, the statement said. Two policemen were wounded and the assailants fled in a car, it said.

In another attack, gunmen fired on a security patrol in Karak, causing no injuries, the statement said.

Armed men also opened fire on a police station in Karak Castle, a Crusader fort, wounding members of the security forces. The statement, made before the standoff ended, said five or six gunmen were believed to have holed up inside the castle.

In all, seven members of the security forces, two local civilians and the tourist from Canada were killed, security officials said. Twenty-seven people were wounded.

Jordan faces homegrown extremism, with hundreds of Jordanians fighting alongside other Daesh militants in Iraq and Syria and several thousand more supporting the extremist group in the kingdom.

Jordan is a key U.S. ally, and a member of a U.S.-led military coalition fighting Daesh.

Over the past year, gunmen have carried out several attacks on members of the Jordanian security forces and foreign trainers. Earlier this year, Jordanian security forces engaged in a deadly shootout with suspected Daesh sympathizers in a northern Jordanian town. In the most recent incident, three U.S. military members were killed in a shooting outside an air base in southern Jordan in November. The three were in Jordan on a training mission, and came under fire while driving into the base.