Police are trying to determine whether they were the victims of a hoax after what they thought was a body inside a sleeping bag turned out to be a life-size doll.

Investigators found what appeared to be a body in a forest in the Izu Peninsula of Shizuoka Prefecture after an anonymous call.

Investigators took the "body" back to the city police station for a postmortem examination without first confirming the sleeping bag's contents, a police spokeswoman said. Apparently no one doubted a body was inside until a medical examiner opened it and found a doll.