A zookeeper was seriously injured Sunday after being bitten in the throat by a tiger.

The 52-year-old employee of Seoul Zoo in Gwacheon, Gyeonggi Province, was found lying half-conscious in a staff passage leading to the cage of the 3-year-old Siberian tiger.

The man identified by his surname Shim appeared to have been delivering food to the cage when the tiger, which had escaped its inner cage, sprung up at his neck.

Shim was found by another staff member and was taken to hospital but is still in a critical condition.

It is still unclear how the tiger escaped but officials say that the lock on its cage is likely to have been left open.

The tiger is reported to have reentered its cage at about 10:38 a.m.

The police are investigating.

By Lee Hyun-jeong
(rene@heraldcorp.com)