Four people who were arrested in Co Limerick yesterday as part of an investigation into the murder of a man in 2010 have been released without charge.

The four people were arrested yesterday as part of the investigation into the murder of Lee Slattery in 2010.

Mr Slattery, a father of one from Ballynanty on the northside of the city, was shot dead and found buried in a shallow grave in a wooded area on the grounds of the derelict Delmege House, which is located on the Knockalisheen Road behind the Moyross estate, on the evening of 31 May 2010.

He had not been seen for the previous four days after he visited a friend's house in the city on the night of 27 May 2010.

A post-mortem examination established he had been shot a number of times before being buried.

Two women in their 20s and 40s and two men in their 20s and 30s were arrested yesterday.

The woman in her 20s was released earlier today and the two men and the woman in her 40s were released this evening.

Gardaí said a file will now be prepared for the Director of Public Prosecutions.