By Dominique Searle

GIBRALTAR (Reuters) - A pack of at least 25 of Gibraltar's famous monkeys are being culled because they are a nuisance and a threat to health in some of the Rock's tourist areas.

Two of the monkeys, a national symbol for the British colony at the foot of Spain, have already been given lethal injections, Gibraltar Tourist Minister Ernest Britto said on Tuesday.

He said the decision had been "a last resort".

Gibraltar's residents have long lived alongside the macaque monkeys, but Britto said the behaviour of one pack had got out of hand in the tourist areas of Catalan Bay and Sandy Bay:

"Children are frightened. People cannot leave their windows open for fear of the monkeys stealing. Apes can bite, and contact with them runs the risk of salmonella or hepatitis."

Last month, he told Gibraltar's parliament that, once the cull of 25 macaques was completed, the overall monkey population would be set at around 200.

Gibraltar has been running a birth control programme to control the monkey population for about six years but it is taking time to work.

Franco Ostuni, general manager of the Caleta Hotel, said guests rooms had been vandalised by monkeys scrounging for food.

"What has to stop is the damage that apes are doing to Gibraltar -- private properties and individuals -- without anyone taking responsibility for it," he said.

However, the International Primate Protection League said it was considering calling on tourists to boycott Gibraltar if it did not stop the cull.

(Reporting by Dominique Searle; writing by Sarah Morris; Editing by Kevin Liffey)