Two youths were arrested and questioned over the weekend in Co Donegal as part of an ongoing Garda investigation into the death of Raphoe man Mr Richie Barron.
Both youths, who are from the local area, were released without charge.
It is believed that members of the team, working under Assistant Commissioner Kevin Carty, are concerned that a car may have been interfered with in Raphoe on the night Mr Barron died.
One of the youths was released on Saturday night and the other was detained in Letterkenny Garda station until early on Sunday morning.
Garda∅ are following a number of lines of inquiry and are planning to interview a number of local people who they believe may have information about a collision with a car now believed to have caused Mr Barron's death.
A post-mortem examination carried out by the State pathologist, Dr John Harbison, in July after Mr Barron's body was exhumed concluded that his injuries were consistent with being struck by a vehicle.
The Garda investigation into Mr Barron's death in October 1996, during which members of the McBrearty family in Raphoe were questioned, led to allegations of corruption against members of the force in the county.
Mr Frank McBrearty and members of his family have taken legal action over the inquiry.