A pizza delivery car was hijacked in a thwarted attempt to attack police officers with a mortar device in Strabane, the PSNI have said.
A 33-year-old man has been arrested.
Detectives are appealing to the public for information after the improvised explosive device (IED) was found in Church View behind the police station on Saturday.
A suspicious object which had been placed on a wall close to a number of houses was discovered by a resident at around 8.30 a.m.
The object was examined by police and ATO and was found to be a viable mortar type device. The device was made safe and was removed for further examination.
Detective Inspector Andrew Hamlin said: “It is our view that that this device was placed in order to attack police officers at the nearby police station but it had the capacity to kill or seriously injure anyone in the vicinity.
"This is not the first time a deadly device has been left in a public space recently and serves to remind us all how little the terrorists responsible care for the lives of local people."
Several homes were evacuated as police dealt with the alert on Saturday.
Sinn Féin MP for West Tyrone Órfhlaith Begley said: “The discovery of a bomb in the Church View area of Strabane must be condemned.
“This was an attack on the entire community. Thankfully no one was injured in this disgraceful incident.
“It only served to bring disruption and fear to the local community in Strabane who reject this dangerous and futile actions.
“Those responsible have nothing to offer society and need to end their attacks against the community.”
DI Hamilton said the pizza car used in the operation was hijacked on Friday night.
"At this time we are linking this incident to the hijacking of a delivery driver’s car in the Mount Sion area at around 9.40pm on Friday evening.
"A fake order was placed with a pizza outlet from a phone box on Bridge Street and when the driver arrived at the stated address, his orange coloured Fiat Sedici was taken from him by three men. It was subsequently discovered on fire at Evish Road around 45 minutes later.
"I am keen to hear from anyone who saw the orange Fiat in the town or who noticed anything out of the ordinary in the Church View area on Friday night. Detectives can be contacted on 101 quoting reference number 371 07/09/19.
"We are continuing to conduct enquiries in the area today and this morning arrested a 33 year old man under terrorism legislation. He remains in police custody at present.”