(CNN) -- Specialist police officers were carrying out a detailed search Friday of a spot in a Scottish forest where something mysteriously exploded this week.
It's still not known what blew up in Garadhban Forest in Gartocharn, about 20 miles northwest of Glasgow, on Wednesday, and Strathclyde Police refused to confirm the nature of the incident.
After receiving a report from a member of the public about what sounded like a blast, police found damage to the wooded area that suggested an explosion had taken place, police said.
Specialists, including scientific and explosives-trained officers, were doing a detailed search of the scene by hand Friday, police said. Experts from other agencies across the United Kingdom, including London's Metropolitan Police, were drafted in to help, they said.
"We can assure everyone that this area is secure and there is no risk to anyone living, working in, or visiting the area," said Chief Superintendent Calum Murray, divisional commander for Argyll, Bute, and West Dunbartonshire.