A pensioner was clubbed to death with an Oriental food crusher after threatening to report his Vietnamese killer to the immigration authorities, the Old Bailey heard.

Ngoc Giam Dang, 74, was asleep in bed in his home at the in Hoxton, when his former lodger Tran Quang Hung, 48, crept into the flat and bashed his head in with the wooden pestle, it is claimed.

Mr Dang, who was also of Vietnamese origin, suffered multiple fractures to his skull and eye socket on July 3 last year and died four hours later in hospital.

Jurors were told he was murdered after a long-running feud with Hung, who he suspected was having an affair with his wife Phu Hang Pham, 48.

Prosecutor Timothy Cray told the Old Bailey: “It is beyond dispute that there was bad blood between the defendant and Mr Dang.

“They did not like each other. There had been a series of arguments and Mr Dang was threatening to report the defendant to the immigration authorities for working illegally in this country.

The two men had also fought in the street a month before the murder and Mr Dang smashed Hung’s laptop computer, the court heard.

Mr Dang’s wife also suffered an injury to her left arm during the attack in Geffrye Court, on the Geffrye Estate, the Old Bailey heard.

When he was arrested two days later Hung claimed he was sleeping rough that night, but CCTV footage showed him entering the block of flats at 1.02am and leaving at 1.07am, and the victim’s blood was also found on his hooded top, jeans and shoes.

Hung, of Mare Street, Hackney denies murder, and now claims he arrived at the flat to find Mr Dang was already dead or dying after being attacked by someone else.

The trial continues.