(CBS) – Authorities were investigating a suspicious package on a No. 82 CTA bus on Chicago’s Northwest Side.

Chicago police say an unattended backpack was discovered on the bus around 4:30 p.m. in the 3700 block of North Kimball. This is at the normally busy intersection of Kimball and Elston avenues in the Irving Park neighborhood.

Police-scanner dispatches indicate a man threw the backpack onto the bus, shouted something and ran off. The bus was then evacuated.

A CTA bus awaits bomb squad investigators at Kimball and Elston avenues. (CBS)

Authorities closed the intersection while the bomb and arson unit removed the item.

Buses along the route were re-routed.