Burglars broke into a zoo and stole five endangered monkeys including a mother and baby marmoset.

Zookeepers say it is a race against time to find the mother monkey Jazz because she could die without medication for an infection.

Her baby, Larkin, is also in danger because he is still dependent on his mother and would not survive long without her.

Staff at Drusillas, near Alfriston, have been devastated by the raid and fear the monkeys could have been stolen to order, perhaps for illegal collectors of rare animals.

Marmosets can fetch up to £3,000 each on the black market.

Raiders smashed their way into the popular zoo park at the weekend and took the marmosets as they slept in their nesting boxes.

One of the boxes contained a family of three of the endangered monkeys, including baby Larkin, born just two months ago, and mother Jazz.

Jazz needs regular medication for an infected jaw and staff fear the worst if she does not receive it.

Larkin's father Captain Jack was also in the nesting box when it was snatched from the marmoset enclosure.

A second box containing Calli and Cartman, two Geoffroys marmosets, was also taken in the overnight raid.

Zoo manager Sue Woodgate said: "We urgently need to find what has happened to them so we can get them back as quickly as possible.

"Jazz must have her medicine regularly or she could die. Because her baby is still dependent on her he would not be able to survive long without her.

"Jazz has had a bone infection for some time but we could not operate on her earlier because she was pregnant.

"We were leaving the operation until after she gave birth to Larkin and was no longer feeding him.

"I am not a vet so I cannot say accurately how long she can survive without her medication.

"But it controls the infection and the longer she is without it the more the lives of both of them are at risk."

She said the marmosets were safe in their enclosure when zoo staff locked up for the night on Saturday at 6pm.

Keepers found the fence to the enclosure had been smashed down when they returned to check the animals just before 8am yesterday.

At first they did not realise that any of the marmosets, which are the size of a guinea pig, were missing.

They rang police at Hailsham to report a break-in but called back a short time later when they realised the two nesting boxes containing the five monkeys were missing.

Sue added: "The people responsible seem to have got over a fence at the back of the park before breaking into the marmoset enclosure. It could be the work of someone who knows what they are looking for and they were stealing to sell on to a private collector.

"Marmosets are very rare and are on the worldwide list of endangered species.

"It is vital that anyone who knows where they are should contact us or the police as soon as possible."

Marmosets are found in the Amazon and other parts of South America.

They feed mainly on fruit and nectar from flowers but also eat small creatures including frogs, lizards and insects.

They are social animals living in groups of between four and 15, spending most of their days roaming their territory searching for food.

Marmosets are among the smallest primates with pygmy species weighing just 100g.

Sussex Police yesterday appealed for witnesses who saw anyone acting suspiciously near Drusillas to contact them.

A spokesman said: "Detectives at Hailsham are investigating a break-in at Drusillas at the weekend.

"Staff there reported the incident to us just before 8am on Sunday but at the time did not think anything was missing.

"They called back a few minutes later to say that five marmosets had been taken."

Anyone with information should phone Sussex Police on 0845 6070999.