Police carried out a routine vehicle stop-check on the main route to and from Valero Oil refinery and Pembroke Power station recently.

The activity was part of Operation Servator - which aims to deter, detect and disrupt a range of criminal activity.

A police spokesman said: "We are asking the public to remain vigilant when in the vicinity of these high profile locations, reporting anything suspicious to Police via 101, or 999 in an emergency."

Residents in the Dyfed-Powys police area should expect officers to arrive at random locations unannounced, and take part in routine patrols for an unspecified length of time as part of the operation.

In the stop-checks on the morning of Tuesday, June 8, drivers were pulled over and spoken to by the Joint Firearms Unit and Pembrokeshire Roads Policing Unit.

Dyfed-Powys Police said: "Project Servator’s patrols are highly visible, but if you see our officers in your area, there's nothing to be concerned about. It's normal police activity and isn't linked to any specific intelligence about a threat to the area."