Gardaí are investigating a number of incidents - including a robbery, threatening behaviour and a stabbing - in Galway City overnight.
At around 2.15am a 38-year-old man reported to the Gardaí that he had been threatened by another man with a knife on the Headford Road.
Gardaí were then told that two other men in their 20's had been robbed and threatened at knife point on the corner of Headford Road.
Two mobile phones and a wallet were taken and the suspect escaped in the direction of Wood Quay.
A man aged 18 was then stabbed in the stomach at around 2.30am on Wood Quay.
He was taken to University Hospital Galway where his condition is said to be not life-threatening.
A number of witnesses described a suspect and Gardaí arrested a 17-year-old teenager fitting the description at 3am in Eyre Square.
He is being held at Galway Garda station under the provisions of section 4 of the Criminal Justice Act 1984 as amended.
Gardaí are appealing for witnesses,or anyone who may have any information to contact Galway Garda station on 091 538000 an incident room has been set up, the Garda Confidential Line on 1800 666 111 or any Garda station.