Swedish detectives could soon have a new weapon in their armoury when investigating rapes - a police dog trained to sniff out sperm.
Police dogs like Xena are trained for a variety of roles
Xena, a five-year-old Belgian Malinois, has spent months being trained for the specialist crime-fighting role.
Her handlers say dogs can be trained to sniff out anything from bodies to bombs, but they have not heard of other forces using dogs in this way before.
Senior officers are yet to decide if Xena can be used in active service.
Captain Lena Thor, of the canine unit of Vastra Gotaland County Police, Gothenburg, said Xena's training started after a request from the criminal investigation team.
"We thought about it for a while then decided to try out a dog we thought was suitable," she told the BBC News website.
"We have a lot of rapes which are outside, in parks, and sometimes it is hard for the victim to tell us exactly where it happened.
Dog's sense of smell is hundreds of times better than human's
Belgian Malinois bred originally to herd and guard sheep
Police dogs also hunt for drugs, explosives and firearms
"We wanted to use a dog to help pick out the place, then take the DNA to be tested and compare to that of the suspect."
Captain Thor said dogs can be trained to sniff out anything from mushrooms and bodies to explosives.
Xena, who is described as a typical police dog - "fond of looking for things and not afraid of anything" - is also trained to search out flammable liquids.
The captain says she will continue with her training while senior members of the force decide whether Xena will be used on duty in real situations.
"But we are very hopeful," she added.