DETECTIVES investigating the gangland murder of Eamon 'The Don' Dunne believe one of his closest associates gave a signal to the gunmen when they entered the pub by leaning down for several seconds to tie his shoelace.

This man was one of Dunne's key lieutenants in his Finglas gang and is from Dublin's northside. One of the main lines of inquiry detectives are pursuing is that the gang boss's murder may have been ordered by a man serving a life sentence for a gangland murder in prison. This man became unhappy when he learned that the notorious criminal had begun a sexual relationship with his girlfriend. As a result, gardaí suspect he arranged his murder, with assistance from Dunne's close associate. However, a source said there were still several other people who could have arranged the 34-year-old's killing, as he was a feared criminal who had many enemies.

Two armed and masked men entered the Faussagh House in Cabra, north Dublin, by the front door at 10pm on 23 April. Dunne was sitting at a table to the left of the door in a large group, including some of his gang members. His 17-year-old daughter is also believed to have been in the pub. Dunne's associate who gave the signal to the gunmen left the public house quickly after the shooting. The signal was designed to show the gunmen where in the crowded pub Dunne was sitting. The associate was among the mourners at his funeral last week.

Dunne was aware his life was in danger and had received at least 10 warnings about his personal safety from gardaí over the last two years. He is thought to have personally ordered 17 gangland murders since 2005. Gardaí regarded him as the most dangerous criminal in the country.

Dunne was part of the gang that murdered Latvian mother Baiba Saulite in November 2006. He also had his boss, Martin 'Marlo' Hyland, killed the following month. He then took over the Finglas-based drugs gang and ruthlessly expanded his empire across the capital, stepping on the toes of several major gangland players.

The fact that he was prepared to murder his own gang associates because of suspicions they might have been plotting against him added to his reputation as a ruthless criminal who would shoot first and ask questions later.

There has been no retaliation since Dunne's murder. This is because his fellow criminals are relieved by his killing because he was so unpredictable and brought so much garda attention to the underworld with the number of murders he organised.