The two men arrested on Friday morning in relation to the explosion at a filling station in Creeslough in October 2022 have been released without charge.
Gardaí say the investigation, led by Gardaí in the Donegal Division, is ongoing with the intention of submitting a file to the Office of the Director of Public Prosecutions.
The two males (aged in their 50’s) had been arrested on Friday morning for alleged offences contrary to the Non-Fatal Offences Against the Person Act 1997.
Gardaí said the men were detained under the provisions of section 4 Criminal Justice Act 1984 at separate Garda stations in County Donegal.
The Garda investigation into the fatal explosion is being co-ordinated from Milford Garda station, where an Incident Room is established under the direction of a Garda Senior Investigating Officer (SIO).