Two people have been arrested as part of an ongoing investigation into the murder of Patrick Heeran.
The 48 year old man was last seen in Mohill in Leitrim eight years ago.
He disappeared without a trace in 2011, but the case was upgraded to murder five years later in 2016.
His body has never been found.
In 2018, his family made an emotional appeal for information on the TV show "crime call", which at the time gardai said received a very good response.
Yesterday afternoon a man in his mid 20s and a woman also in her mid 20s were both arrested in the midlands area and are being detained at Tullamore garda station.
The man is being held under section 4 of the Criminal Justice Act where he can be held for 24 hours.
The woman is being held under Section 30 of the Offences against the State Act, where she can be detained for up to 72 hours.
Gardai say the investigation is ongoing.