Hong Kong  - An investigation was under way Wednesday into why a giant panda in Hong Kong bit the female keeper who had been looking after him for seven years.

The keeper was hospitalized after being bitten on the leg by giant panda An An, whose name means Peace in Chinese, in his enclosure at the Ocean Park theme park in Hong Kong on November 30.

The attack by the 22-year-old panda only came to light after a video of it taken with a mobile phone camera by a park visitor was circulated on the internet video channel YouTube.

Footage of the incident shows the 100-kilogram panda rushing back to its enclosure while the park worker, who has not been identified, lies on the ground with an injured left leg.

The woman, who was still recovering in hospital Wednesday, is understood to have breached safety protocols by refilling a supply of bamboo in the enclosure while the panda was out of its den.

She has been panda keeper since 2001 and has worked at Ocean Park for 15 years, park officials confirmed.

No action has been taken to move the panda, which remains in its enclosure and can be watched by visitors, but an investigation was Wednesday continuing into the reasons for the incident.

An An is one of two giant pandas presented to Hong Kong in 1999 as part of a gift from China to mark the former British colony's return to Chinese rule two years earlier.

Giant pandas are not regarded as aggressive animals but have been known to attack humans to protect their territory if they feel it is under threat. (dpa)