Armed robbers who hijacked a taxi and threatened post office staff at gunpoint in Londonderry made it over the border into Donegal, police have confirmed.
The men abandoned the stolen silver Volkswagen Passat after carrying out the robbery in the Culmore area on Monday morning.
Police have now confirmed the two men made off on foot towards Muff via Kilderry Lane, and disappeared into Inishowen.
It is thought possible they were later picked up in another vehicle.
Army bomb disposal specialists examined the stolen car but no device was found.
The two robbers are described as both being approximately 5'8” tall and stocky build.
One was wearing a black coat with a hood and the other was wearing a dark coat over a grey hooded top.
Police want anyone in the Coney Road area or Muff and may have seen the men either on foot or getting into another vehicle to contact them.