A convicted killer who was freed early from his life sentence has been jailed again after he was caught dealing heroin during a police sting.

Francis McNeilly, 48, admitted being involved in supplying the drug at Livingston Sheriff Court on Wednesday.

McNeilly had been jailed for life at the High Court in Edinburgh in 1981 after being convicted of murdering a West Lothian man who drowned in his own blood after being battered to death.

A jury returned a majority guilty against McNeilly after he knocked William McIlwraith, 22, to the ground outside a Bathgate nightclub before repeatedly banging his head off the pavement. McNeilly was released on licence in 2002.

In December last year police raided his home in Fauldhouse, West Lothian, and recovered the heroin.

The court heard that McNeilly sent undercover cops a text message telling them he could supply them with heroin. His home was raided and police found a quantity of the drug.

McNeilly's lawyer told the court how his client's past had now caught up with him. He said that McNeilly had received threats over false claims he was a police informant as up to 20 other drug dealers were also arrested during a series of test purchases by Lothian and Borders Police.

Sheriff Donald Ferguson jailed McNeilly for four months, but admitted the punishment paled in comparison to the recall of his licence.

Sheriff Ferguson said: "This is a serious matter in its own right. To a certain extent there is very limited sentencing open to this court due to you being recalled on licence."

McNeilly will now be kept in jail until at least February 2011.