The PSNI said it could not release information regarding anyone’s profession, but confirmed she was arrested on suspicion of “causing death by dangerous driving” and “driving while unfit through drink or drugs”.
The 40-year-old woman, thought to be off-duty at the time, was driving a Sabb Vector which was said to have collided “head on” with Mr Mills’ Toyota Yaris near Omagh on Saturday night.
Both parties were taken to hospital after the Dromore Road incident was reported to police shortly after 10pm.
Sadly, Mr Mills died from his injuries.
The woman was also treated in hospital for injuries that were “non life-threatening”.
Police said her Saab Vector may also have been involved in a collision with a white Peugeot 207 earlier that evening.
Inspector Stephen Humphries is appealing for witnesses.
“We have spoken to a number of witnesses however we know that other motorists who have not yet come forward were travelling on the road last night and they may have information that could assist in the investigation,” he said.
“We would also like to speak to anyone who may have witnessed an earlier collision between the Saab and a white Peugeot 207. The number to call is 101.”