Members of the Pima County Regional Bomb Squad carry x-ray equipment and scans during a call today about a suspicious package left in the parking lot of a motel in South Tucson. The surrounding area was evacuated and a portion of South Sixth Avenue was closed.

A suspicious package found in a South Tucson motel Tuesday morning turned out to be a bag of gypsum from the 1960s, police said. 

A maintenance worker found several packages in a  shed of the Arizona Motel, 1749 S. Sixth Ave., took one of them out and dropped one of them near the Paradise Motel, 1701 S. Sixth Ave., Lt. Jeff Inorio a South Tucson police spokesman said in a news release. 

The cloth bag was filled with powder, wrapped in plastic and had a wire protruding from it, the release said. 

The Pima County Regional Bomb Squad and Tucson Fire Department hazardous materials unit was asked to help with the investigation. 

A bomb technician examined the package and took a sample of the powder which was determined to be gypsum. 

Authorities determined the packages were used in the 1960s to line trenches before water pipes were placed in the ground and the wire was attached to magnesium to prevent the pipes from corroding, the release said. 

A portion of South Sixth Avenue was closed for about two and half hours during the investigation.