Beirut, Asharq Al-Awsat—Lebanese authorities have implemented new security plans at the country’s largest prison, including placing “dangerous” prisoners in solitary confinement, after police raided the detention facility following reports that the prison had become an “operations room” for the Islamic State of Iraq and Syria (ISIS).

Lebanese security forces raided Roumieh prison, east of Beirut, on Monday, following reports of communications between prisoners and perpetrators of a suicide bombing in Tripoli which resulted in the death of nine people. Prison authorities uncovered smuggled cell phones amid claims that ISIS-linked prisoners are ordering and coordinating attacks in Lebanon while being held in the facility.

“The new security strategy is based on isolating dangerous prisoners from the outside world,” sources told Asharq Al-Awsat.

Authorities have removed “dangerous” prisoners from B block—the prison’s notorious Islamist wing—and placed them on a new solitary confinement wing, pledging to tighten up security in the facility. B block holds approximately 900 prisoners, including more than 300 designated as terrorists by security forces.

A total of 17 Roumieh prisoners have been categorized as “dangerous” and moved into solitary confinement, including a prisoner nicknamed “Abu Turab,” said to be the leader of the Islamist prisoners in Roumieh. Abu Turab, a Jordanian national, was among the Fatah Al-Islam prisoners arrested in the Nahr Al-Bared case, according to local media reports.

The majority of Roumieh’s “dangerous” prisoners are non-Lebanese nationals and include a number of prominent jihadist figures such as Abu Obeida, another Fatah Al-Islam member, who reportedly acted as an enforcer on the cell block, threatening other prisoners with violence if they failed to conform to strict Islamic guidelines. Lebanese authorities said that the new security arrangements in Roumieh prison aim not just to protect the outside world from the “dangerous” prisoners, but also their fellow detainees.

The latest security measures came after Lebanon’s Interior Minister Nihad Mashnouq told reporters that Lebanese authorities had intercepted communications between Roumieh prisoners and the perpetrators of Saturday’s bomb attack in the northern city of Tripoli.

Mashnouq stressed that any prison officer or guard found to be involved in the smuggling of cell phones into the prison will face the severest of punishments.

“If one cell phone enters the new prison block, the head of the officer responsible for that will be cut off,” Mashnouq warned in remarks published Tuesday by As-Safir.