Four chimpanzees euthanised after escape from Swedish zoo

A fifth chimpanzee is thought to be on the loose

The animals were euthanised due to a lack of tranquilizer (AFP via Getty Images)

Four chimpanzees made an escape from their enclosure in a Swedish zoo and went on the run, before they were captured and euthanised on Wednesday, Swedish media reports.

The animals apparently had to be euthanised due to the fact that there was not enough tranquilizer for them all, Annika Troselius, press spokeswoman for the group that operates the Furuvik zoo, told the Swedish newspaper Expressen daily.

She explained that chimpanzees are strong and dangerous animals and the main focus of the zoo was “is that no human gets hurt”.

A fifth chimpanzee is also believed to have left its enclosure and to be on the loose, Ms Troselius told Swedish radio.

There were, however, no other immediate details on this.

It was not clear how the animals managed to escape from their enclosure.

The Furuvik zoo is located near to the city of Gavle, 165 kilometres (100 miles) north of Stockholm, and was home to a total of seven chimpanzees.

It forms part of an amusement park, and, according to its web page, is also the only primate research station in the Nordic countries.