A woman has been arrested on suspicion of possessing explosives after her car was stopped and searched next to London's Olympic Park, British police said on Wednesday.

Police said they were not treating the incident as terrorist related, but gave no further explanation.

The 40-year-old woman was stopped in a car park near the Olympic complex in east London on Tuesday by police who were acting on information.

The park is where the main stadium, velodrome, aquatics centre, athletes' village and other key venues are sited.

Another car was stopped on a motorway and properties were searched in London and Kent, southeast England, but no further substances were found.