A man is being questioned by gardai following the incident at Rosie Hackett Bridge on Monday afternoon | FILE PHOTO
"A man, aged in his 30s, was subsequently arrested and is detained pursuant to Section 4 of the Criminal Justice Act 1984 at a Garda Station in the Dublin city area," said a garda spokesperson who added that the scene was preserved for a technical examination.
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Investigating gardaí are appealing for witnesses to come forward and any person who may have been in the vicinity of Rosie Hackett Bridge between 4pm and 5pm on Monday is asked to come forward.
Gardaí say they are particularly interested in speaking with anyone who may have information or any mobile phone footage of the incident.
"Any road users who may have camera footage, including dash-cam, and were travelling in the area at the time are asked to make this footage available to investigating gardaí," said a spokesperson.
Anyone with information is asked to contact Store Street garda station on 01 666 8000.
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