Danielle's parents made an emotional appeal

Danielle disappeared after leaving home to catch a bus to school on Monday 18 June, and there has been no trace of her since despite appeals by the police and her parents.

Two of Danielle's female school friends sent her a text message just after 8am when she failed to catch the school bus but received no reply, Mr Coltman told a briefing at Tilbury police station.

The last positive sighting of her came shortly before when two boys from her school St Clere's secondary school in Stanford-le-Hope, saw her walking towards the bus stop.

A girl matching her description was then seen getting into a dark blue Transit-type van, apparently without "hesitation".

Several hours later a text message believed to be from her mobile was received.

Public response

Officers have been searching a landfill site near her home on Thursday.

They are expected to give details of how the public can get involved in a wider search over the weekend.

Police have mounted an internet appeal

The police have ruled out a suspected sighting of Danielle in Lancashire, where a young woman fitting the schoolgirl's description was seen at a hotel in Blackpool.

Checks with friends she met on a school field trip in the West country have also thrown up no fresh leads.

An Essex Police spokeswoman said there had been a "terrific response" from the public with more than 300 calls to a special hotline.

A home video tape of Danielle has also been released in the hope that it will provide a clue to her whereabouts.

Danielle's parents Linda, 41, and Tony, 40, have made an emotional plea for help in finding their daughter.

Children at St Clere's have also been urged to contact police if they have any information.

Danielle - who lives with her parents and younger brother - is 5ft 7in, slim, with blue eyes and long blonde hair and a brace on her teeth.

On Monday morning Essex Police released a man from Thurrock, Essex, whom they had been holding on suspicion of abduction.

The man, who is in his early 40s, was freed on police bail until 22 August.