"The Merseyside Police Force were involved with the scare at the Grand National and obviously with the additional worry over the Drumcree situation they are extra keen not to take any chances," he said.

"It is better to be safe than sorry and we want to ensure there is no disruption to the Open Championship as there was at Aintree in 1997. It is simply an extra precaution," he emphasised.

Police Superintendent, Val Barker, said " Our commitment is to the public safety and the security operation is to reassure the public.

"It is certainly not in response to any specific threat. This is a large sporting event and we are keen that everyone enjoys their time at Royal Birkdale.

"The policing of the event and the overall security operation underlines our on-going commitment to public safety"

Tiger Woods set out with his usual four security men with him after a number of death threats during his career.

The police spokesperson advised people to arrive at the course in plenty of time since cars were likely to be searched as they enter the course.

Closed-circuit television is also in use around the course.