The daughter of bus stop stalker Levi Bellfield said she is “convinced” he killed Surrey schoolgirl Milly Dowler and is now willing to testify against her father.

Bobbie Louise Wilkinson spoke out yesterday after former wheelclamper Bellfield, jailed for life last year for killing students Amelie Delagrange, 22, and Marsha McDonnell, 19, and the attempted murder of Isleworth student Kate Sheedy, admitted driving a car linked to the 13-year-old’s disappearance.

His daughter told Five News she remembered her father acting strangely around the time when Milly went missing.

She said: “He went straight to the bedroom - the main bedroom, it was his bedroom - and he was in there for a few minutes and then I went to walk into the door to see when we were going and he just slammed the door shut and snapped at me ‘Just wait two minutes, we're going in two minutes’.

“He didn't want me to come into the bedroom, he was definitely hiding something in that bedroom. I don't know what it is, but he was definitely hiding something.”

Bellfield, who bludgeoned his victims to death after they got off buses in south west London, became the prime suspect in Milly’s murder after officers spotted a red Daewoo driving past the spot Milly was last seen and matched it to a car his girlfriend owned at the time.

The Walton schoolgirl disappeared just minutes before the red car is picked up by CCTV cameras. Her skeletal remains were discovered six months later in Yately Heath Forest in Hampshire.

The brutal killer has always denied killing Milly but in an interview from his Wakefield Prison cell, Bellfield, 40, told the Daily Mirror he was driving the car caught on CCTV.

His 18-year-old daughter previously refused to testify against her father but has now said she is determined to help in any way she can.

She said: “I think I've got the courage. Even if I haven't got the courage I'm just going to be strong to try to get that, try and help the police so Milly's family get justice.”

A Surrey Police spokesman said officers will investigate Bellfield's involvement in the murder.

He said: “Operation Ruby, the Surrey Police investigation into Milly Dowler’s murder, is a vigorous and live inquiry.

“Speculation can be unhelpful and potentially hurtful to Milly's family, but we will thoroughly investigate any new lines of enquiry.”