PORTLAND — Several offices in downtown Portland were evacuated this afternoon after workers in a federal Social Security office reported a suspicious package to authorities.

Deputy Fire Chief David Jackson said the package, a large brown envelope, was stained and appeared to be leaking. But when members of the Fire Department’s HazMat team opened the envelope, they found paperwork and a compact disc.

Jackson said that shortly after 3:30 p.m. authorities evacuated the upper floors of the office building at One Portland Square. It is located at the corner of Spring and Union streets.

Emergency personnel were at the scene for more than three hours, until about 7 p.m.

Jackson said the process took some time because the police department’s bomb squad had to make sure there were no explosives in the package. Firefighters then checked the package for biological or chemical substances.