A MIDNIGHT deadline passed with no word from an abductor who may have taken schoolgirls Holly Wells and Jessica Chapman.

A dramatic "call me" plea was issued on TV and radio by the police officer leading the hunt for the missing ten-year-olds, Detective Superintendent David Beck.

He urged the abductor to ring by midnight last night, saying details of a hotline number were in messages sent to Jessica's Nokia mobile phone, not seen since the best friends vanished 12 days ago.

In his appeal, which has been constantly repeated on TV and radio - every five minutes by one local station - Mr Beck said: "Work with me to stop this getting any worse than it is. You do have a way out."

Detective Chief Inspector Andy Hebb said: "We don't know with certainty that Holly and Jessica have been abducted, and therefore are not unduly anxious about the fact that no call has been received. If someone is holding the girls, it is possible that they don't have access to Jessica's phone and therefore could not access the message left by Mr Beck.

"We will reconsider our options later today, once we have taken expert advice about how this line of inquiry may be progressed.

"Our optimism about finding Jessica and Holly alive remains as strong as it was on day one of this inquiry.

"The fact that we have not received a phone call from a possible abductor has not changed that."

Yesterday, Mr Hebb said there were many positive lines of inquiry apart from the phone appeal. He refused to elaborate for operational reasons but emphasised that the investigation - one of the biggest of its kind mounted in the UK - was "most certainly not back to square one".

Police still believed the girls, from Soham, Cambridgeshire, were alive, he said.

The parents of the schoolgirls last night made another appeal through police for the safe return of their daughters.

Mr Hebb said: "Holly and Jessica, your parents still love you. They want you back safe and well."