In this Dec. 8, 2011, file photo, the Amtrak Downeaster passenger train travels through Portland. Credit: Robert F. Bukaty | AP

A suspicious package — later determined to be a bag of personal belongings — left at a South Portland rail yard caused delays for the Amtrak Downeaster Sunday afternoon while police investigated.

Workers found a suspicious item attached to a rail car entering the Rigby Rail Yard about 12:46 p.m., and after consulting with Boston and Maine railroad police, South Portland police were called in to assist, South Portland police Lt. Thomas Simonds said Sunday.

That package was near other rail cars marked as containing hazardous material in the southwest corner of the yard, so Simonds said that South Portland firefighters and the police department’s bomb squad also were called in to provide additional assistance.

An examination determined it was a bag of personal belongings that Simonds said was likely left by someone who trespassed on the rail yard property.

“Today, the South Portland Police were called to assess a suspicious item seen attached to a rail car, due to the proximity to rail cars containing hazardous materials, an abundance of caution was used to determine that the package was harmless,” he said.

The incident caused long delays for the Amtrak Downeaster between Portland and Boston, according to the Portland Press Herald. Amtrak attempted to hire buses to keep rail travelers on schedule, but a cruise ship in Portland hampered those plans, the newspaper reports.

Train traffic resumed by 4:30 p.m.