Inspector-General of Police Razarudin Husain said the five, aged 19 to 62, were rearrested under Sosma with their remand orders ending today.

Razarudin previously linked the attacker, identified as Radin Romyullah Radin Imran, to the Southeast Asian terror organisation Jemaah Islamiyah. However, he later said this theory was based on Radin’s father’s past association with the terror group.

Radin’s father is among the five being held under Sosma.

“Our suspicions that the father is a Jemaah Islamiyah member is confirmed. That is already in our data and records,” he said at a press conference in Kuala Lumpur.

“However, after calling up 47 witnesses, we found that (Radin) had no ties whatsoever with Jemaah Islamiyah, although his father did, according to our data.”

Razarudin said the family’s neighbours told the police that Radin and the family isolated themselves from others, with even his children not enrolled in school.

“They are rooted in radical beliefs and ideologies,” he said.

Radin killed two constables – Ahmad Azza Fahmi Azhar and Syafiq Ahmad Said – and injured a corporal before he was shot dead at the scene.

The attack was followed by several unrelated incidents, including a death threat to a DAP MP, and two men trying to trespass into Istana Negara, as police moved to tighten the level of security at government buildings, high-traffic areas and key facilities.

In a special address on Tuesday, Prime Minister Anwar Ibrahim also vowed a strong response to the terror attack, while seeking to assure the people that “things will be under control”.