Gardaí confirmed the men, aged in their 50s, were arrested for alleged offences contrary to the Non-Fatal Offences Against the Person Act 1997.
Both men are currently detained under the provisions of section 4 Criminal Justice Act 1984 at separate Garda stations in County Donegal.
The arrests related to the ongoing investigation into the explosion at the service station and apartment building on 7 October 2022.
Four men, three women and three young people, ranging in ages from five to 59, died in the blast.
Robert Garwe and his five-year-old daughter Shauna Flanagan-Garwe, Catherine O’Donnell and her 13-year-old son James Monaghan, Jessica Gallagher, Martin McGill, James O’Flaherty, Martina Martin, Hugh Kelly and 14-year-old Leona Harper were all killed in the explosion.
Gardaí added the investigation into the fatal explosion continues, co-ordinated from Milford Garda station, where an Incident Room is established under the direction of a Garda Senior Investigating Officer (SIO).The investigation continues to be led by local Gardaí in the Donegal Division, supported by the Garda National Bureau of Criminal Investigation (GNBCI) and other agencies, including the Health & Safety Authority (HSA) & the Commission for the Regulation of Utilities (CRU).