In the aftermath of the 2001 September 11 attacks in the United States , the ERU became a member of the ATLAS Network , a European Union ( EU ) organisation consisting of 32 special police units across Europe . More recently , the ERU has been deployed to trouble spots in Dublin City and Limerick City in a combined Garda effort to tackle gun violence , resulting in a 92 % decline of firearms offences related to organised crime . Regular uniformed Gardaí ( police officers ) in Ireland are unarmed
September 11 attacks
September 11 attacks
Garda Emergency Response Unit