EMERGENCY services across Hampshire, the Isle of Wight and along the south coast were thrown into chaos last night when BT's telecommunications services experienced a "massive power failure" in Southampton.

Tens of thousands of telephones across the county including lines in Portsmouth and into parts of Wiltshire went dead when the power supply to a communications centre at Bargate in Southampton crashed out of action.

Emergency services including police, fire, ambulance and coastguards were affected by the crash at around 6.40pm.

Calls were diverted to Dorset police as the true scale of the emergency emerged. At one point, it is understood that the Dorset force could only communicate using e-mails.

Police chiefs were today in talks with telecommunication experts after the 999 backup facility at Netley failed to activate as expected.

Mobile phone networks also became jammed during the chaos which crippled the telephone network across the county.

People needing hospital treatment were told to go straight to Southampton General Hospital where some faced a five-hour wait for treatment.

All senior medical staff were contacted and put on standby while others had a taxi sent to their homes to tell them to turn on their mobile phones.

Director of nursing Katherine Fenton said: "We immediately went on an internal alert but in addition to that we went halfway towards a major incident.''

Police stations across Southampton and Hampshire remained open throughout the night and the force put extra officers on patrol.

Hampshire Fire and Rescue Service also put all of its 34 retained stations across the county on standby and drafted in an extra 20 officers to its headquarters to cope with the chaos.

The coastguard also established coastal patrols during the emergency and placed lookouts on cliff tops across the region.

Southampton's police chief, Superintendent Graham Wyeth said: "In my long service history, this is the first time I have seen such a large scale failure of this nature."

He added that police were coping "well" with the emergency and advised anyone experiencing problems dialling 999 to contact their local police station directly.

Police reported some phone lines across the county were back in operation by around 10.55 pm. The service was totally restored by the early hours of this morning.

Hampshire Fire and Rescue spokesman, Dave Askew, said a pre-arranged emergency plan came into force as soon as the chaos broke-out.

He said: "We have had partial failures but nothing on this scale before."

BT spokesman, Eric Barr, said the problem occurred when there was a massive power failure at one of the company's network centres at Bargate in Southampton.

He said that BT engineers had identified where the problem was and were working as quickly as possible to restore the network to normal.

He said: "As far as police, fire and ambulance calls are concerned we have diverted their calls to neighbouring authorities. Obviously we are doing everything we can possible to get services restored to normal."