Sharks have been let off the hook for September's huge internet outage in China. Marine experts initially thought that a shark dining on the main trans-Pacific cable linking China to the US was responsible for the break.

However, in the absence of reliable witnesses China Telecom has decided that a more likely suspect is a Shanghai Xinhai Air Shipping Company (SXASC) vessel. China Telecom is now suing the company for more than £20m in compensation.

It is believed that a ship's anchor cut the two undersea fibre-optic cables, which are underneath a shipping lane operated by the SXASC. But the company maintained that other ships were in the area and that it was not its vessel that cut the cable.

This was the third time that the cable was cut, the first being in February, and shark attacks have not been ruled out in those cases.

"We have known sharks to eat tyres before," said marine biologist Dr Brenda Kemp. "We think it is because they confuse them with small seals."