BT has confirmed that one of its telephone exchanges in central London was robbed in the early hours of Wednesday morning, leading to massive telephone and internet outage for its customers.

"We can confirm there was a break-in at our Mayfair Telephone Exchange last night (Wednesday), this is now an ongoing police investigation and therefore we are unable to comment further," said the former UK telecoms incumbent.

"BT apologises for any disruption caused to our customers. Our engineers are working around the clock to ensure that full service is up and running as soon as possible," the carrier added.

"We were called out at 1am in the morning to a report of burglary at Farm Street, W1," a Metropolitan police spokeswoman told Techworld. "It is believed that technical equipment has been stolen. Officers from the Westminster CID are investigating, with no arrests at present."

It seems that the police were alerted by an alarm at the exchange, and according to the Register, routers, networking cards and fibre have been pilfered.

BT is not the first carrier to have been hit by equipment thefts, especially as copper and fibre are increasingly pricy commodities. Nowadays, copper costs over $8,000 (£4,500) per ton, and in some countries, such as South Africa, theft of copper from telephone lines is a frequent occurrence.

Back in July, the Financial Times website, FT.com, was knocked offline after the theft of equipment at a Cable & Wireless hosting centre. The online shopping site of Sainsbury's was also affected, by the theft. Optical wiring, routers, servers and switches were removed from the site by thieves, who police believe were after scrap metal.

According to the Samknows website, BT's Mayfair exchange serves 3,010 residential premises, and 4,274 non-residential premises in central London.