Officers warned residents of the small northern village of Oldeberkoop, 87 miles north-east of Amsterdam, to stay inside until the tigers could be caught and returned to their shelter.

Police spokesman Nathalie Schubart said the sanctuary's outer fence is not fully secure.

She said the tigers - named Radjah and Dehli - needed to be caught because they may have escaped through the fence, "which would be dangerous for the people nearby".

There were no reports of injuries.

Police later tweeted that one of the tigers had been hit with a tranquiliser but it had not had the desired effect.

"Still trying to tranquilise the animals," they added.

Just after 1pm BST, police tweeted that the tigers were both under general anaesthesia.

Oldeberkoop is home to the Felida centre, which receives big cats from circuses and zoos, treats them, and works to replace some in a larger shelter in South Africa.

According to its website, the centre's residents include two lions, eight tigers, a black jaguar, and a leopard.

Radjah and Dehli were rescued from a zoo in north Germany whose owner could no longer afford to feed them.

Newspaper De Telegraaf reported that the tigers appeared to have escaped through a gate which had been left open accidentally.