A special memorial service was held at Cork University Hospital this evening for the relatives of the 329 people who died in the Air India disaster twenty years ago.
More than one hundred staff involved in the recovery and identification operation after the plane was downed in a bomb attack, were also there.
The anniversary ceremonies will continue tomorrow when President McAleese joins relatives at the memorial at Ahakista in west Cork.
Earlier, senior members of the Royal Canadian Mounted Police force unveiled a plaque thanking the gardaí for all their help in the wake of the disaster.
The bronze plaque was received by Assistant Commissioner Adrian Culligan at the Cork divisional headquarters at Anglesea Street.
The plaque is in recognition of efforts by the gardaí during the recovery operation and the subsequent 18-year investigation into the bombing.
Two men were acquitted in March of any involvement in the bombing.
One man is serving a five-year sentence for manslaughter.
