Gardaí said a man in his 40s has been arrested in connection with the hit-and-run investigation.
A mother of one killed in a hit and run in Co Donegal was shopping for her wedding dress hours earlier, a friend has said.
Named locally as Laura Connolly (34) she was returning home from a family party in Lifford at about 2.45am on Sunday when she was struck by a white van.
Gardaí are searching for the van driver who they say did not stop and remain at the scene.
Jason Barr, an SDLP councillor in neighbouring Strabane and friend of Ms Connolly, said she had earlier in the day been shopping for a wedding dress for her upcoming marriage next year.
“My heart goes out to her son, her fiancé, her mother and father and her brothers and the wider Connolly family and her friends,” he told The Irish Times.
“It is just devastating. This is something you just don’t expect to hear.”
Paying tribute to Ms Connolly, he said she was “such an outgoing personality”.
“She lit up the room when she walked into it,” said Mr Barr, who met Ms Connolly at a socially distanced pandemic bingo event a year and half ago.
“Her nickname for me since was All the Fours, 44,” he said.
“That was Laura, always good with the craic. There was never a dull moment with her, never, she just loved her family, her friends and the craic.
“She lived every day as best she could.”
Ms Connolly looked after her teenage son as well as her father, according to Mr Barr.
With strong family connections in Strabane too, Mr Barr said both towns “are in mourning”.
“I hope the person who did this comes forward or the guards get them, to give the family some closure,” he added.
“A hit and run is very sore on a family. It just shows you how precious life is and how it can be taken away from you with the click of a finger.”
Emergency services attended the scene on the N15 at Townparks, Lifford, and Ms Connolly was taken by ambulance to University Hospital Letterkenny where she was pronounced dead.
Gardaí said the van and its driver did not remain at the scene and have yet to be located.
The man is being questioned under Section 4 of the Criminal Justice Act at Letterkenny Garda station.
Gardaí appealed for witnesses and anyone with video or dash cam footage from the scene and along the route to come forward.