A ceremony has been held in Enniskillen, Co Fermanagh, to commemorate the victims of the explosion at the town's war memorial 25 years ago.
An IRA bomb killed 11 people and left 63 injured. A 12th person spent 13 years in a coma before he died.
No one has ever been charged or convicted in relation to the bombing.
Police in the special Historical Enquiries Team have recently carried out a fresh investigation and have given a file to the PSNI.
Appeals were made at the ceremony for assistance with the new police inquiry into the bombing.
Stephen Gault, whose father was one of the 12 people who died as a result of the explosion, said he was encouraged that officers of the Historical Enquiries Team have reviewed the evidence.
He appealed to anyone with information about the IRA bombing to pass it onto the PSNI or gardaí.
During the service, local Northern Ireland Assembly member and DUP chairman Maurice Morrow called on the PSNI to press ahead with their investigation so that relatives can learn if those responsible for the explosion might be brought to justice.
An account given by Gordon Wilson of holding the hand of his fatally injured daughter, Marie, in the rubble at the Cenotaph is one of the most enduring memories of The Troubles.
The estimated 40lb (18kg) bomb had been planted close to the War Memorial and exploded as people gathered to remember the dead at the 11th hour on Remembrance Sunday.
At 10.43am today, the bells of local churches rang 12 times, once for each of those who died.