The sister of Yvonne Heap, who died after being found with multiple stab wounds outside an Oxford police station, has spoken of her family's heartbreak.

Ms Heap, 38, was found in a blue Citroen car outside Cowley police station last Saturday afternoon, with wounds to the heart, face and torso.

She underwent emergency surgery, but died at the John Radcliffe Hospital on Monday.

The mother-of-three was born in Londonderry, Northern Ireland. She was a manager at Ladbrokes bookmakers in Hollow Way, Cowley, Oxford, around the corner from Sunnyside, the road where she had lived until about six weeks ago.

Her sister, Mairead Carney, 40, of Sandford-on-Thames, said: "I feel like a massive chunk has been cut out of our lives. She was my best friend -- we are all completely heartbroken.

"She was a happy, warm, kind person who loved being with people. She was very outgoing, with a strong personality, and people came to her in a crisis.

"We spoke every day, socialised together, went on holiday together and were huge parts of each other's lives.

"We went to Barcelona for my 40th birthday, and were already planning hers next year. The next big thing we were planning was our children's communion.

"My son Luke, aged seven, and her son Tomaz, eight, and 11-year-old daughter Yasmeen are all having their first communion in June. That will still go ahead, with a big party as she planned.

"Being a mum was the biggest thing in her life."

Nahed Akhter, 40, yesterday appeared at Oxford Crown Court accused of killing Ms Heap. Akhter, of Sunnyside, Cowley, was remanded in custody until June 27. He will face a charge of murder.

An inquest into Ms Heap's death was opened and adjourned yesterday (May 2).