BERLIN—The U.S. consulate in Berlin was evacuated as a precaution Thursday after an employee reported a strange smell from an envelope, but police said no dangerous materials were found in a sweep of the building.

The smell came from an envelope containing supporting materials for a visa application that was given to consular employees by the applicant in person, U.S. Embassy spokeswoman Ruth Bennett said.

Police experts checked the building to see if any chemical substances or poisonous gases had been released but nothing was found, police spokesman Michael Merkle told n-tv television.

Bennett said she had no immediate information on the status of the person who brought the envelope in, and Merkle would not comment, citing the ongoing investigation.

The U.S. Embassy is located in downtown but the consulate is in the southwestern Zehlendorf suburb.