At about 12.30pm, the injured woman was listed in stable condition in hospital.

The alleged attack happened in the couple’s flat at Po Yan House on the Po Lam Estate at about 1.30am.

“The man called police saying his wife suffered burns at home,” a police spokeswoman said.

She said the man and his injured wife were found inside the flat when officers arrived.

“Police were told the woman was suffering badly from her illness and her husband wanted to end her life,” a police source said.

“Initial investigation showed that after he started the fire, he changed his mind, doused the flames to save her and then called police.”

One neighbour said the couple had arguments over their relationship in the past and she was bedridden after suffering a stroke a few years ago.

“Her husband quit his job as a kitchen worker to take care of his wife at home,” a woman neighbour said.

She said the couple had children who had moved out of the flat.

The case was initially classified as wounding and later reclassified as “attempted murder” at 1pm.

The elderly man was being detained at Kwun Tong police station for questioning and had not been charged, according to police.

Detectives from the Kwun Tong district crime squad are investigating.

Police figures showed there were 11 reports of homicide in the first six months of this year, a 15 per cent drop from 13 in the same period last year.