Amman - Militants behind an attack on Jordanian police supported Daesh and investigations had revealed plans for more attacks on security and civilian targets, Jordan’s interior minister said on Monday.

Jordanian police said on Saturday a homemade explosive device planted near a police van killed a policeman and injured six others the day before.

The police vehicle had been maintaining security near a music festival in the majority Christian town of Fuheis, near the capital Amman and 15km from the hillside city of Salt.

In a huge security operation, Jordanian forces laid siege to a building in a residential part of Salt on Saturday night in search of those responsible for the bomb attack.

After the suspected militants refused to heed calls to surrender, the security forces stormed the building in a shoot out that resulted in the death of three militants and four security personnel, police said.

Ten members of the security forces were also injured.

Interior Minister Sameer Al Mobaideen said the militants, who blew up part of the building when the security forces stormed it, did not belong to a specific group but subscribed to Daesh ideology.

King Abdullah warned on Saturday the perpetrators of the attack would pay dearly.

The monarch has been among the most vocal leaders in the region in warning of threats posed by radical groups.

The group were all Jordanian and there were no signs so far they had foreign links, Al Mobaideen said, refusing to give names of suspects. “The investigations are secret and ongoing,” he told a news conference.

Alongside automatic weapons in the suspect’s possession, the authorities found a location where chemical ingredients for manufacturing explosives were buried, he added.

General Hussain Hawatmeh, head of Jordan’ Gendarmerie, said the militant cell was recently set up and there were indications its members had embraced radical ideology.