Victorian Police officers are seen inside Flagstaff train station in Melbourne, Australia, March 28, 2019. AAP Image/James Ross/via REUTERS

SYDNEY (Reuters) - The morning commute for Australians in the country’s second largest city was thrown into chaos on Thursday after armed police stormed a train station in response to an erroneous sighting of a gun.

Trains at Melbourne’s Flagstaff Station were suspended shortly around 8am local time (2200 GMT), while commuters were urged to stay clear of the local area.

“We had a concern that it might be someone with a firearm on a train,” Graham Ashton, Victoria Police commissioner told 3AW radio station.

“There was no fire arm on the train.”

Trains resumed around an hour after the first report, Public Transport Victoria said, though major delays have now been reported.

A staunch U.S. ally, Australia has been on heightened alert from 2015 for attacks by home-grown militants returning from fighting in the Middle East, and its intelligence agencies have stepped up scrutiny.

In November, a Somali-born man set fire to a pickup truck laden with gas cylinders in the center of Melbourne, killing one, before he was shot by police in a rampage they called an act of terrorism.