Three more animals have died at a zoo in Brazil, as the hunt for the apparent animal killer intensifies.
An orangutan was among the latest three animals to die
An orangutan, a European bison and a camel are the latest to die at the Sao Paulo zoo, Brazilian news services say.
The autopsies performed on another 10 animals which died between 24 January and 6 February have shown the presence of a highly toxic rat poison.
Two kangaroos have also died in recent weeks at a zoo in Brasilia, sparking fears they too could have been killed.
The latest deaths at the zoo in Agua Funda, Sao Paulo, have reinforced suspicions that the animals were deliberately killed.
Traces of three different types of rat poison were found in the cages of the animals that died, and a highly toxic - and illegal - poison called sodium fluoroacetate showed up in autopsies.
Police suggest the killer has a background in chemistry. They also suggest he or she may be a disgruntled former employee with detailed knowledge of the zoo's routines.
Interviews have been carried out with officials, vets and directors at the zoo.
Police investigators are to be joined by expert detectives and scientists from the zoology department of Sao Paulo state university (Unesp) as the hunt to find the culprit is stepped up.
Meanwhile, in a zoo in the capital, Brasilia, officials are investigating the deaths of two kangaroos, Jumper and Lucky, since 9 January.
A spokesman said they had died from eating rat poison.