Garda Public Order Units were deployed to Crumlin in Dublin on Halloween evening after fireworks were thrown at gardaí.
A woman was also injured by a firework at a private residence in the area.
Officers were on patrol on Cashel Avenue in Crumlin on the evening of Friday 31 October when fireworks and missiles were thrown at uniformed gardaí, who were forced to withdraw.
Public Order Units were deployed to the area and assisted Dublin Fire Brigade to safely attend the scene.
Just after 6.30pm, gardaí became aware of a report that a firework had been discharged at a private residence.
A woman in her 30s was treated at the scene and brought to St James's Hospital for serious but non life threatening injuries.
Gardaí are appealing for any witnesses who were in the Cashel Road area between 5.45pm and 6.45pm on the evening of 31 October to contact them.
Anyone who has camera footage from the area during that time is also asked to come forward.
Crumlin Garda Station can be contacted on 666 6200. The number for the Garda Confidential Line is 1800 666 111.
