More than a dozen Patas monkeys were killed after the roof in their enclosure collapsed as a result of a devastating fire at Bedfordshire Park's African Forest.
The fire was reportedly caused by a faulty generator and although three crews from Bedfordshire Fire Brigade attended and extinguished the fire, the poor animals could not be saved.
A spokesman for the park said: "Staff and fire crews attended the scene; however, devastatingly for everyone at the park, none of the 13 animals could be saved."
All the other inhabitants of the park are being observed, but early signs suggest that they have not been affected by the fire.
In the wild, Patas monkeys live in grasslands and open savannah in central Africa. They can grow up to 34in (85cm) in length, with a 30in (75cm) tail and can live for up to 20 years.