SINGAPORE - Policeman Iskandar Rahmat was on Friday (Dec 4) sentenced to hang after he was convicted by the High Court of both charges in the Kovan double murders.

The 36-year-old was expressionless as the court found him guilty of murdering car workshop owner Tan Boon Sin, 67, and his son Chee Heong, 42, at the older man's Hillside Drive house on the afternoon of July 10, 2013.

Mr Shashi Nathan, Iskandar's lawyer, said his client will appeal the sentence.

Delivering his verdict in a packed courtroom of about 60 people on Friday (Dec 4), High Court Judge Tay Yong Kwang rejected Iskandar's defence and found that he had attacked them "cruelly and relentlessly with the clear intention of causing death".

Justice Tay also found that Iskandar intended to kill the older Mr Tan as part of his plan and found that Iskandar had brought a knife along. Iskandar had claimed that his original intention was to grab the money and run out to the main road to hail a taxi, but Justice Tay said this "inane plan" was unbelievable.

The judge also did not believe Iskandar's story that the older Mr Tan would suddenly turn into a knife-wielding man after welcoming him to his home.

As for the younger Mr Tan, the judge found that he became "collateral damage" and that Iskandar formed the intention to kill him there and then to silence him.

Debt-laden and facing a possible expulsion from the Singapore Police Force, Iskandar had planned to rob the older man, but things went awry when Mr Tan allegedly discovered the ploy.

While Iskandar did not dispute the killings, he has maintained throughout the trial that Mr Tan had attacked him first with a knife, and that he had reacted in self-defence by stabbing and slashing his victim after wresting the knife away.

And when Mr Tan's son entered the house and charged at Iskandar with clenched fists, he retaliated by swinging the knife wildly.

Both the prosecution and defence's closing statements were made on Nov 23.

Pointing to the multiple knife wounds suffered by both men - mostly in the vital areas of the head, neck and chest - the prosecution argued that Iskandar had intended to kill both men.

Deputy Public Prosecutor Lau Wing Yum's case was that Iskandar had wanted to silence the duo so they could not identify him.

In turn, Mr Nathan had urged the court to accept his client account that he killed in self-defence in a sudden fight, and to convict him of culpable homicide not amounting to murder.

Mr Nathan also argued for Iskandar to be convicted of murder under Section 300(c) instead, if his defences were rejected.