Image caption Constable Philippa Reynolds, 27, died in the overnight crash

Two men have been arrested after a policewoman was killed in a crash involving a stolen car in Londonderry.

PSNI Constable Philippa Reynolds, 27, died in the collision on the Limavady Road at 03:40 GMT on Saturday.

Constable Reynolds was on a routine patrol in an unmarked police car. It is believed a stolen silver 4X4 vehicle drove through a red light before hitting the police car.

Her commanding officer Stephen Cargin said her colleagues were "devastated".

Killed instantly

Constable Reynolds, from the greater Belfast area, was a back seat passenger in the police car.

The PSNI believe she was killed instantly by the impact of the stolen vehicle.

Two officers who were also in the police vehicle were both hurt but were not seriously injured.

Constable Reynolds was a former teacher who had joined the PSNI two years ago.

Police investigating the crash arrested two men, aged 23 and 25, in the Derry area at about lunchtime on Saturday.

Media playback is unsupported on your device Media caption The BBC's Julian O'Neill said the suspected stolen car may have run through a red light

The Police Ombudsman has been informed of the incident.

'Bubbly personality'

The PSNI Chief Constable, Matt Baggott, paid tribute to the officer and vowed to bring those responsible to justice.

"It is with great sadness that I learned of the death of our colleague. This is a personal tragedy for her family and also for the whole Police Service," he said in a statement.

"She was out on duty, working to keep people safe, when she died. My thoughts and prayers are with her family at this time."

Mr Baggott added: "I and my colleagues will ensure that no stone remains unturned as we work to bring to justice those who perpetrated this crime".

PSNI district commander Stephen Cargin said Constable Reynolds was "in the prime of her life, beautiful, friendly".

"(She was) one of the most enthusiastic officers, just a really bubbly personality, somebody who wanted to be a police officer," he said.

Image caption The constable's family released this picture to the media, as it "reflects her bubbly personality"

'Tragic waste'

"Her colleagues are devastated, as I am as her commander, as we are as a police service, but she just typifies her colleagues - out there doing a good job."

Secretary of State for Northern Ireland Theresa Villiers said it was a "tragic waste of a young life in sad and reckless circumstances".

Northern Ireland's first and deputy first ministers also expressed sympathy.

In a statement, Peter Robinson and Martin McGuinness said: "Officers in the PSNI put their lives at risk on a daily basis to serve and protect our community and we are all truly grateful for their dedicated service.

"Those who commit a crime such as vehicle theft must realise their actions can have serious consequences."

'Shocked'

Justice Minister David Ford said his thoughts and prayers were with the woman's family.

"I also send my best wishes to the two officers injured in this incident for a speedy and full recovery," he said.

"It is hard to imagine how they, and indeed the wider PSNI family, are feeling."

Chairman of Northern Ireland's Policing Board, Brian Rea, said he was shocked by the incident.

"To lose a colleague, out on patrol protecting the community, is a terrible blow to the PSNI," he said.

SDLP MP Mark Durkan said the policewoman had been "tragically killed in the line of duty whilst doing her job to protect the community".

I and my colleagues will ensure that no stone remains unturned as we work to bring to justice those who perpetrated this crime. Matt Baggott, PSNI Chief Constable

'Dangers'

"The shock felt across the community will be matched with disgust that such criminal activity has led to this tragic death, and I call on those responsible, or anyone who has any information, to come forward to the PSNI," Mr Durkan said.

Ulster Unionist Ross Hussey said: "This young woman's death in the line of duty serves to re-emphasise the dangers faced by the officers of the Police Service of Northern Ireland on a daily basis, as they put themselves in harm's way to protect the whole community."

The Republic of Ireland's most senior police officer, Garda Commissioner Martin Callinan, also expressed his condolences.

"Our thoughts and sympathies are with our friends in Northern Ireland as they mourn the loss of their colleague," he said.

"We also wish a speedy recovery to the officers injured in the incident."

Appeal

The police have asked witnesses to contact them.

Ch Supt Cargin said: "I would like to appeal to anyone who has information and may have seen the silver land cruiser travelling between the Gobnascale and Limavady Road areas between 03:00 GMT and 03.30 GMT, or if they saw the two people who fled the scene and ran off towards the Ebrington area.

"Anyone with any information, no matter how small, please call us. These were officers who were out serving their community and we want the community to help us and give us the vital information we need."