Four of the five monkeys stolen from Blackpool Zoo have been found.
The four monkeys were found on a doorstep in West Yorkshire three days later; however, one baby monkey is still missing.
Charlotte Pennie, head of primates at Blackpool Zoo, collected the animals.
She said: “We are extremely relieved four of the monkeys have been found safe and well, although we are also saddened the baby cotton-top tamarin has not been found.
“The monkeys have all been checked and reintroduced back into their group.”
Police said the robbery was well organised and there was “definitely a market for monkeys“.
The animals can fetch thousands of pounds when sold on the black market, both in the UK and abroad.
PC Steve Higgs said: “We were inundated with calls from members of the public.
“This is still a live inquiry as we continue to investigate who was responsible for the thefts.”