A woman who saw her partner murdered in Dublin's latest gangland killing tackled the gunman, pulled off his balaclava and scratched his face before being shot in the leg.

Sharon Rattigan (27), is recovering at her family home in Drimnagh after her boyfriend Shay O'Byrne was shot three times in the back in Tallaght on Friday night.

O'Byrne (27), was a key player in an ongoing drugs feud between two Drimnagh-based gangs which has now claimed 13 lives.

Gardaí believe that O'Byrne was murdered by members of a gang led by criminal 'Fat' Freddie Thompson. Three of Thompson's associates are currently in custody.

Detectives from the Organised Crime Unit spotted the three men driving in a car on Friday afternoon. Witnesses described seeing a similar car speed away from the murder scene and the trio were arrested at 11.30pm, three hours after the shooting.

Detectives have interviewed Sharon Rattigan and say that they are confident that she got a good glimpse of the gunman and will be able to identify him.

She was shot after attempting to wrestle the gun off the masked man. Gardaí say she is lucky to be alive. The suspect dropped the murder weapon, a revolver, during the struggle and it is hoped that forensic experts will be able to extract DNA from it. It is also likely that Sharon Rattigan has the killer's DNA under her fingernails and this could also prove crucial.

Sources say they already have a good idea who pulled the trigger. O'Byrne was ambushed in a car outside his home at Tymon North Park in Tallaght at around 8.40pm. Although he was regarded as the number two in the Drimnagh gang, he only had a handful of criminal convictions.

Both Shay O'Byrne and Sharon Rattigan had been previously targeted as part of the ongoing feud. In August 2005 gardaí found a note during the search of a house in Portarlington, Co Laois which identified potential targets and named both O'Byrne and Rattigan.

Sharon Rattigan's brother Joseph was shot dead outside the family home as part of the same feud in July 2002. He was the third victim of the dispute which is now set to escalate because, previously, relatives and girlfriends of gang members have largely been regarded as off limits.