Gardaí are pursuing 300 lines of enquiry following the murder of a 30-year-old man and a mother of six in Ballymun in Dublin.
The incident happened at Balbutcher Drive on Wednesday. Gardaí have recovered a second weapon in their investigation into the double murder.
Antoinette Corbally, 48, was shot several times at the front of her mother's home on Balbutcher Drive as the intended target, her convicted gunman brother Derek Devoy, fled the scene.
The second victim was Clinton Shannon, a locksmith from Swords, Dublin, and a friend of Derek Devoy's. He was hit by a number of bullets as he sat in a car on the street outside the property.
It is understood the weapons located by gardaí - a handgun and a submachine gun - were located in one of two partially burnt-out vehicles. Gardaí are particularly interested in the movements of the cars.
A large Garda presence remains in place in Ballymun, and armed patrols have been deployed.
Chief Superintendent Lorraine Wheatley described the victims as innocent and said officers were investigating more than 300 lines of inquiry since the broad daylight attack.
She thanked the local community in Ballymun for their support in the aftermath of the incident.
And she said: "I believe that there's lots of other information out there that may assist with this investigation.
"An innocent young man and a mother-of-six have been killed and we are appealing for the community to come forward."
Detectives are trying to trace the movements of two cars used in the attack - a silver Opel Zafira with 08 LS 3101 registration plates, and a black Volkswagen Golf GTI with 06 LH 3466 registration plates.
A handgun and an automatic weapon, understood to be a machine gun, were used in the killings.
The front of Ms Corbally's house was riddled with bullets.
Gardaí said additional armed patrols have been operating in the Ballymun area amid fears of retaliation for the murders.
"If people have any information on the intent to commit more crimes we would like them to come forward," Chief Supt Wheatley added.
Derek Devoy, known by the nickname Bottler, is believed to have been the target of the shooting and was released from jail in 2015.
He has convictions for a drive-by shooting in Ballymun, more than 10 years ago, and armed robbery.
His sister is not the first in the family to face a gangland onslaught.
His brother Mickey was shot dead and his body dumped in a lane in Tallaght, Dublin, in early 2014 after he had been freed from prison.
It is understood the brothers have been embroiled in long-running feuds over several years which have been linked to drug dealing, debts and personal disputes with rivals.
The latest incident was not being linked to the bloody gang war involving the Kinahan and Hutch crime gangs, which has seen more than 10 murders in Ireland and overseas in recent years.`
Anyone with information can contact the Garda confidential helpline on 1800 666 111.