Meanwhile a woman arrested in connection with the robbery is still being questioned.
The two men have been held at Tralee and Killarney garda stations in relation to the Waterville Post Office robbery since being arrested on Wednesday under Section 30 of the Offences Against the State Act, 1939.
Killarney gardaí will today seek an extension of their detention at a scheduled sitting of Cork District Court today.
Meanwhile a third person arrested in connection with the raid is still being questioned.
Gardaí have confirmed that a woman in her late 20s was taken into custody last night, and is being detained at Killarney Garda station under Section 30 of the Offences Against the State Act, 1939.
The armed raid took place at Waterville post office on Wednesday morning, and two Gardaí were injured when their car was rammed in pursuit of the suspects.