The sister of an Oxford mother murdered by her estranged partner has claimed that Thames Valley Police has not learned the lessons from her death.

Today would have been Yvonne Heap's 40th birthday. She died after Nahed Akhter repeatedly stabbed her outside the city's Cowley police station in April last year. She had previously told police several times that her life was in danger.

Yvonne Heap In May, Akhter, of Sunnyside, Cowley, was jailed for her murder. Ms Heap's sister Mairead Carney, 41, of Sandford-on-Thames, said the police were still not handling domestic violence complaints properly.

She criticised the force over an assault on an 18-year-old family friend in September. She claimed the teenager spoke to three different police call-handlers asking for help. Each ended the conversation and hung up.

Mrs Carney said they should have showed more concern for her welfare and remained on the line.

Police were more worried about searching Cowley for the offender than going to the young woman's aid, she claimed.

A police spokesman said the victim had not wanted to lodge a complaint of assault.

Oxford police said in the 12 months to the end of October there had been 844 domestic violence incidents, 177 more than in the previous year.

But a spokesman said the force, with other organisations, was raising the profile of domestic violence and encouraging victims to come forward.

Oxford police is expanding its domestic violence unit at Cowley from four Pcs to six, with a victim support worker seconded to the team.

Linda Manning, of Oxfordshire Women's Aid, said anecdotal evidence from victims showed both "good and bad" experiences of police called to incidents.