SINGAPORE - The suspect in Wednesday's double murder in Kovan is a veteran police officer, the Singapore Police Force announced this morning (July 13).

Iskandar Rahmat, 34, is a senior police officer attached to the Bedok Police Station but was suspended at the time of the grisly double murder of Tan Boon Sin and his son, Tan Chee Heong, in the Kovan area. He fled to Malaysian on the night of the murder, and has been extradited back to Singapore. He arrived at Police Cantonment Complex at about noon today.

Iskandar, who joined the police force in March 1999, was facing internal disciplinary action and was in debt, the police said. He was barred from carrying out duties and carrying firearms as per protocol, during his suspension.

"The case is especially troubling as the suspect is a police officer," Deputy Prime Minister and Minister for Home Affairs, Mr Teo Chee Hean, said at a press briefing this morning.

Police are still investigating the connection between Iskandar and Tan Boon Sin, but revealed that the two had crossed paths before.

"We do not know the extent of their relationship, but we do know that, in November 2012, Tan Boon Sin went to Bedok police station informing them that he was a victim of theft," Mr Hoong Wee Teck, Deputy Commissioner (Investigations and Intelligence) and Director of Criminal Investigation Department, said.

"The suspect was the duty investigator at the time, but he was subsequently reassigned."

Iskandar was arrested by Malaysian police at a restaurant in Danga Bay, in Johor Bahru, around 11.30pm last night. He had crossed the Causeway on a scooter around 11pm on Wednesday, the same day the two bodies were found.

"We first established (Iskandar's) identity on Thursday morning after piecing together several pieces of evidence," said Mr Teo.

"We had not earlier released any details for operational reasons as police assessed that there was no threat to public safety, and revealing his identity was likely to have made his arrest more difficult to achieve.

"The actions that the suspect has been accused of have tarnished the reputation of the police. His actions, if proven, have abused the trust placed in him, and betrayed his colleagues in the police force who serve faithfully and dutifully."

Commissioner of Police Ng Joo Hee added that he "cannot remember the last time a murder suspect was also a police officer".

Mr Ng added that the the fact that suspect was an officer spurred police to hunt him down.

"Tragically, Tan Boon Sin and Tan Chee Heong are dead. And untold grief has been brought upon their families and loved ones. Their loss can never ever be made good," said Mr Ng.

"I wish that there is something the police can do to lessen their anger and sorrow. I wish that I could turn back the clock and undo this great misfortune that has befallen the Tan family. But I know that no amount of commiseration or regret will lessen the hurt.

"All we can do is to bring the culpable to justice, and to mourn with the rest of Singapore the senseless loss of two innocent lives."