British police are investigating several suspicious "items" discovered close to a highway that could be related to the plot to blow up airliners, Sky News reported Thursday.

The items were not believed to be explosives, but Scotland Yard refused to discuss what the items are or whether they are linked to any ongoing operation by its Anti-Terrorist Branch.

However, Sky News was told that several "bags" were found and that they could be connected to the alleged plot to blow up airliners. Some 16 people have been charged in relation to that plot that involved setting off liquid explosives on a number of international flights.

The items were found by members of the public on a highway near High Wycombe in Buckinghamshire, where some of the arrests took place.

A police spokesman said: "Explosives officers attended the scene as a precautionary measure." They were later joined by forensics officers.