About 5.am on Sunday, three young men obtained a shopping trolley and played in it before placing it about 12-metres up on an arch of the Balclutha Bridge, overhanging State Highway 1. As a result, one lane of traffic was closed by police until the trolley could be retrieved safely by crane.
Senior Sergeant Chris Wakelin, of Balclutha, said the stunt was captured on CCTV, and police were seeking community help identifying the culprits.
Although the incident could be perceived as harmless horseplay, the consequences could have been serious, he said.
"This is a serious incident, placing a heavy object precariously on a narrow bridge on the busy State Highway 1.
"If it were to fall down, it could have caused serious injury or death, given there’s nowhere for traffic to go to evade it."
Contact police on 105, or Crimestoppers 0800555-111.