A murder inquiry has been launched by detectives investigating the disappearance of missing shop worker Jenny Nicholl.

The search to find the 20-year-old has become a hunt to catch her killer, police say.

Major new clues was revealed yesterday as senior officers said Miss Nicholl, from Richmond, North Yorkshire, probably knew the murderer.

The young woman was last seen by her parents on June 30 when she left saying she planned not to return that night.

She failed to turn up for work two days later and was reported missing on Monday, July 4.

Her car was found in the car park of the Holly Hill pub, on the outskirts of Richmond, the same day.

Detectives say two friends received text messages sent from Miss Nicholl's phone from the Carlisle area on July 9.

Her father, Brian Nicholl received a message on July 14 sent from the Jedburgh, in the Scottish borders.

Detectives believe these may have been sent by the killer.