Gardai investigating the fatal stabbing of a 31-year-old man in a central Dublin pub visited a number of houses and flats in the north of the city yesterday.
They were hoping to question a man, also in his early 30s, who spent a good part of Thursday evening drinking with the victim, Mr Patrick Costello, from East Wall.
According to witnesses, the two men had a row which developed into a fist fight which was broken up by staff at the Plough pub in Marlborough Street.
One man was ejected from the bar. It is understood he went to a house in the East Wall area and returned to the pub with a knife. He then stabbed Mr Costello in the chest.
Mr Costello died from blood loss a short time later.
Gardaí went to a house in East Wall but the man they were seeking was not there. Later they visited houses and apartments in a north Dublin estate.
Gardaí said the killing developed from a drunken row.