The pair have been on the run since last May when Paton failed to appear at Norwich Crown Court and Stacey breached the conditions of her licence.

The Ford Granada they were driving was found on a slip-road near Dundee at the end of June, and since then police in Norwich have been liaising with their counterparts north of the border.

Detective Inspector Beresford said, “I still believe them to be in Scotland, and I am confident that we will get them.”

The detective said that the duo had neither been arrested on other matters nor started claiming benefits, which is often how people are traced.

He believes they are using false identities and have found work, adding, “We do not think they are having contact with anyone this end, or I suspect we would’ve heard of it by now.”

Former prostitute Stacey was jailed for life in 1998 for the murder of a six-month-old boy from North Walsham after he was left in her care.

He died as the result of a serious brain injury caused by being violently shaken.

Stacey’s murder conviction was reduced to manslaughter in July 2001 at the Court of Appeal and her sentence was reduced to seven years.

She was released on licence from prison in November last year, with terms including that she reside at an address in Norwich.

However, she sparked a national police hunt in May when she breached the conditions of her licence and went on the run with Paton.

Her licence has since been revoked and she has been recalled to prison.

Paton, who is said to have extensive connections in Scotland, is also being sought by police after failing to appear at Norwich Crown Court on May 6.

He was facing charges of kidnap, false imprisonment, possession of a firearm and blackmail, relating to a 31-year-old female.

Paton is described as white, six feet tall, with short grey hair.

He generally uses a wheelchair as he has difficulty walking.

Helen Stacey is described as white, 5ft 5 inches tall, with curly brown hair.