People were evacuated from their West Dunbartonshire homes after “ordnance” was found in a shed.
The item was found just before noon on Tuesday at Beeches Road in Clydebank.
Emergency services were dealing with the incident with a 100-metre cordon around the area.
A Police Scotland spokeswoman said: “We received a report of ordnance found in a shed on Beeches Road, Clydebank, around 11.55pm on Tuesday October 15 2019.
“A 100m cordon and appropriate traffic management plan has been put in place.
“People have been evacuated from nearby houses and we are asking people to stay away from the area while emergency services deal with the incident.
“Explosive Ordnance Disposal (EOD) will attend to check the item and make it safe.”
Later it was confirmed a controlled explosion would be carried out in a nearby field, with residents warned they might hear it.
The cordon was lifted just after 3pm.