Two men wearing balaclavas threatened staff at a post office at gunpoint before fleeing with cash.
Gardai have launched a manhunt after the armed robbery in Clara, Co Offally on Wednesday morning.
It's understood the two suspects were carrying a firearm and knife during the incident which happened at around 9.30am.
The pair fled the scene in an 07 registered Silver Toyota Avensis which was later found on fire on Kilbeggan Road.
Detectives believe they left the scene of the blaze in a dark hatchback car.
A garda spokesman said: "Gardaí are investigating a robbery from a post office that occurred at approximately 9.30am this morning Wednesday 18th December 2019 in Clara, County Offaly.
"Two males in balaclavas entered the premises with what's believed to be a firearm and a knife and threatened staff. They left the scene with a sum of cash in a Silver Toyota Avensis (07 D registered). This car was discovered on fire on the Kilbeggan road on the outskirts of Clara a short time later."
