Home minister Saifuddin Nasution Ismail said the investigation is ongoing.

“(Their detention) allows the investigation to continue. They have the option of engaging a lawyer,” he told the media at the police training centre here today.

Earlier, Saifuddin presented posthumous promotions to the relatives of policemen Ahmad Azza Fahmi Azhar, 22, and Syafiq Ahmad Said, 24, who were killed in the attack.

Several other policemen who survived the attack were also given promotions.

On May 17, the 21-year-old suspect stormed into the police station armed with a gun and a parang and killed the two officers. Another policeman was injured in the 2.45am incident.

The assailant, who was shot and killed at the scene, was previously suspected by police of being a member of Jemaah Islamiyah (JI), but Saifuddin had denied the claim.

JI co-founder Abu Bakar Bashir also denied any links with the attack, and strongly condemned it.

Meanwhile, Saifuddin warned against exploiting the debate on citizenship applications, saying it is the norm for representatives from the government and opposition to receive requests for help to solve citizenship issues.

Saifuddin pledged to help those qualified to obtain citizenship under the law.

“Don’t exploit this issue (and make it out to be) a coordinated movement to give out citizenships in bulk,” he said.

Early this month, Stulang assemblyman Chen Kah Eng was criticised after his service centre planned to hold a citizenship briefing and information session on June 30.

He said the briefing was to tackle problems faced by the public in applying for citizenship and birth certificates due to reasons such as parental negligence.