Another man was also shot in the incident.
Gardai are believed to have been looking for both firearms and drugs as part of the planned search in which a garda was shot in Ballymun this morning - writes dublinlive.ie.
Just before 8am, a planned search took place on Barnwell Drive in Ballymun in which a garda and another man were shot.
It is understood that a garda and man were both shot in the arm.
Gardai are believed to have been looking for both firearms and drugs as part of the planned search.
It is believed that the suspect came toward the ERU and fired a shot. A second member of the ERU returned fire and hit the suspect.
A source said: "It was all over in about four seconds."
Local councillor Noeleen Reilly told Dublin Live earlier today: “It’s terrible that a garda was injured in line of duty. It’s very worrying. There have been a number of incidents in recent months, and it has escalated. There’s no question that Ballymun needs additional resources, on the ground. Not just armed. I really hope that those involved make a full recovery. People in the area are in total shock over this.”
In a statement, Minister for Justice Charlie Flanagan said: "I learned with concern this morning that a member of An Garda Siochana was shot and injured in the course of a Garda operation in North Dublin. I wish him a full and speedy recovery. Incidents like this highlight the danger that can face members of An Garda Siochana in carrying out their duties.
"The work of uniformed Gardai and the special units is critical in keeping people safe and tackling serious criminals whose activities can destroy communities. I acknowledge the good work of An Garda Siochana and assure the force of my continued support for its efforts."
In a statement, a garda spokesman said: "Gardai in Ballymun are investigating a shooting incident in Ballymun on the 7 December 2017.
"The incident occurred during a planned search of a house in Barnwell Drive. Two people have been injured, a Garda and male civilian, both were treated at the scene by trained Gardai and DFB. They have taken to hospital for treatment. Their injuries are not believed to be life threatening.
"We have no further information at this stage an update will be issued in due time.
"GSOC have been notified of the incident. Investigations are ongoing."
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