Two women have been held hostage while a gang stole a large sum of money from a sub-post office in County Tyrone.
Three armed men forced their way into a flat at Lower Main Street, Strabane, and held two women hostage overnight.
One of the women was then taken to Donegal and the other was ordered to drive to the post office, remove money and hand it over to a gang member.
Both women were traumatised by the incident. Police suspect dissident republicans were behind the raid.
The incident began at about 0130 BST on Monday and the women, one of them a post office employee, were held hostage for several hours.
The employee was later ordered to drive to her place of work and remove the money.
She then took the money in a taxi to the church car park at Doneyloop in the Republic of Ireland and handed it over to one of the gang members.
The other woman was later released in Donegal.
Detectives want to hear from anyone who saw suspicious activity at Lower Main Street at about 0130 BST, or saw anyone waiting around at the church car park between 0900 BST and 0930 BST.
The number to call is 0845 600 8000, or Crimestoppers on the confidential freephone number 0800 555 111.