Gardai confronted a gang of marauding thugs who allegedly launched a stabbing and then a robbery just minutes apart in a busy city centre.
The group first struck on Wednesday evening in the Temple Bar area of Dublin city.
Sources have said that a man was stabbed by a youth in a dispute in the busy tourist mecca.
Then in a second incident just a short time later the gang are suspected to have launched an attack on a group of tourists on Grafton Street.
A source said: "The guards were watching them on CCTV as they fled from Temple Bar to Grafton Street.
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"They were completely out of control and armed units, the Armed Support Unit, rushed into intercept them.
"The armed gardai from the ASU confronted them and cornered them and they were forced to surrender without a fight.
"This was just a collection of young bullies terrorising people, it could have been a horrific incident, but the ASU and Pearse Street Gardai were there very quickly."
Gardai have confirmed they are investigating the incident.
A spokeswoman said: "Gardaí are investigating a serious assault on a man. The incident occurred on Cope St D2 on the 18th April at midnight.
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"The injured party in his 20s was taken to James Hospital with non life threatening injuries.
"A youth was later arrested in relation to the incident and an incident of public order on Church Lane.
He was taken to Pearse St Garda station."
