GARDAÍ investigating the deaths of a man and woman whose bodies were recovered from Dublin's Grand Canal believe they may have died in a tragic accident.

Early indications suggest that the man and woman in their late 20s were homeless and were heroin users.

In the preliminary examination of their bodies, there were no visible signs of foul play in their deaths, such as stab wounds or head wounds.

Sources stressed that the investigation was still at an early stage and nothing could be ruled out.

While gardaí did not wish to speculate too much on the cause of death, the possibility that the man and woman, a mother of two, overdosed on heroin before ending up in the canal at Suir Road in Inchicore was being examined. Post mortems by state pathologist Dr Marie Cassidy are scheduled to take place today at the City Morgue in Marino.

Officers said another possible explanation for the deaths was that either the man or the woman fell into the canal and the other person then tried to assist.

Temperatures plummeted on Friday night. One of the bodies was discovered by a passerby at midday yesterday by the bank of the canal.

The man and woman were said by local gardaí to frequent the Grand Canal at Suir Road on a regular basis as well as other parts of the city.

Neither of the victims carried identification and attempts were underway this weekend to confirm their names so contact could be made with their families. Both are believed to be Dublin city natives.

The scene was yesterday preserved and the Garda Technical Bureau were examining the area.