Updated: THE police investigation into the mystery disappearance of York woman Mandy Bishop was stepped up as teams of divers searched the River Ouse.

An underwater search and rescue team from Humberside Police was drafted in yesterday to scour the river for the 34-year-old agoraphobic, who was last seen on March 22 having previously not left her house for 13 years.

Frogmen will also today conduct an underwater search of a five-mile stretch of the River Ouse between Skeldergate Bridge and Naburn Locks.

PC Bob Southwell, of the Humberside Underwater Search Unit, said: “We have been in the search dinghy up and down the river from 10am, carrying out a visual search of the river and its banks.

“On Thursday, the team will be back in York carrying out underwater searches. We will begin these searches on the west bank at Skeldergate Bridge.

“This kind of search is a lot more time consuming, but depending on the river flow we will try and cover a similar area.”

As well as suffering from severe agoraphobia, Mandy had also recently made threats to kill herself.

Police were yesterday continuing forensic searches of her house, where traces of blood had been found. Tests are ongoing to determine whether the blood relates to Mandy and has any significance.

Mandy, who is the sole carer for her cancer-stricken mother, Valerie Bishop, was reported missing by a family friend at 1pm last Saturday, but it is thought she may have gone missing 12 days earlier.

Police have not yet said why it took so long for her to be reported missing.

Mandy is white, with green eyes, about 5ft tall, and of a very petite build, wearing size eight clothes, and has shoulder-length dark-brown hair. She usually wears trousers and a jumper with a black or red coat.

Anyone with information should phone North Yorkshire Police on 0845 6060 247, quoting reference number 12100051110.

Alternatively, phone Crimestoppers anonymously on 0800 555 111.