Ramkarpal said the intention to cause death cannot be ruled out as the incident took place at a time when the occupants were at home.

He called for the incident to be investigated from all angles because the timing of the attack indicated a possibility that more harm was intended.

“The perpetrator(s) chose to commit the offence at a time when the victims were asleep and helpless. As such, the intention to cause death cannot be ruled out,” he said in a statement.

Ramkarpal also said the investigation must include whether the perpetrators were induced or incited to commit the offence by statements made by “irresponsible parties”.

“In which case, those parties can be prosecuted under Section 505 of the Penal Code,” he said.

On Wednesday, police arrested a man to assist their probe into the Molotov cocktail attack on the Perak DAP leader’s home.

Perak police chief Yusri Hassan Basri said the man, in his 30s, who was arrested in Shah Alam, Selangor, did not have a criminal record.

The fire had damaged Ngeh’s three vehicles on Wednesday morning. A bottle, believed to be a Molotov cocktail, was found at the scene.

The case is being investigated under Section 435 of the Penal Code for mischief by fire.

Ngeh was reported to have said that those behind the fire might have been instigated by others, and misled by falsehoods created by PAS and Bersatu over a statement he made on Dec 28.

His statement courted controversy by suggesting that non-Muslim constitutional experts be appointed to the committee studying the conflicts between shariah law and the Federal Constitution.

Ngeh later apologised, saying he was unaware the committee had actually been formed by the National Council for Islamic Affairs, chaired by the Sultan of Selangor.