The elderly mother of a man suspected of murdering Asian waiter Surjit Singh Chhokar in a "very serious" condition in hospital following a "horrific attack" in her own home.

Mary Coulter, 76, is being treated for two broken arms, serious head injuries and facial lacerations after she was attacked by four men who forced their way into her home in Overtown, in Wishaw, North Lanarkshire.

She is the mother of Ronnie Coulter and grandmother of his nephew Andrew Coulter who were cleared of murdering Mr Chhokar in 1998.

The waiter was stabbed to death outside the home he shared with his girlfriend in Overtown.

The murder, which has been dubbed "Scotland's Stephen Lawrence", sparked controversy after the failure of authorities to secure a conviction.

Three men were cleared of the killing following separate trials.

Mrs Coulter was disturbed in her home in Overdale Place, Overtown, at 5.20am yesterday.

The men attacked her in her hallway, before pursuing her onto the street and continuing their assault.

They ran off when her scream alerted neighbours.

Police have said the break-in was not a robbery, and they are trying to establish why the woman was targeted.

Detective Inspector John Lamb of Strathclyde Police said: "I am almost speechless at the level of violence directed at an innocent elderly lady.

"It beggars belief that anyone could subject a woman, particularly an elderly one, to such a mindless horrendous attack.

"The victim, who lives alone, will require a great deal of medical care and attention to recover from these injuries.

"This was not a robbery and we are trying to establish why these men targeted this woman.

"I would urge anyone who was in the area, heard anything or has any information regarding those responsible to get in touch.

"It is imperative that we trace those responsible."

The suspects are described as white men. They were either wearing hooded tops or had their faces hidden with scarves. One was described as particularly heavy built. All were wearing light-coloured trainers.