Passengers are advised to check flight details before travelling

All eight police forces have been granted stop and search powers, which allow officers to investigate any person or vehicle.

However, there are no immediate plans to introduce new anti-terror laws.

There is still some disruption to the country's transport network, although delays and cancellations are easing.

Glasgow Airport is now fully operational.

All terminals and car parks have reopened although the airport forecourt remains closed.

Some flights have been cancelled and passengers are being advised to check with their airline before setting out.

Passengers are being asked to travel to the airport by public transport and to allow extra time for their journey because of road works on the M8 motorway.

There have been long delays on the A8 approaching Edinburgh Airport, where the forecourt is still closed to private cars.

Passengers are being strongly advised to allow extra time for their journey to the airport and wherever possible to use public transport.

All flights are scheduled to leave, although some have been delayed.

Cars are not allowed onto the forecourt at Prestwick Airport.

Passengers are being advised to allow extra time to get through additional security inside the terminal.

All flights are operating as normal.

The forecourt at Aberdeen Airport is still closed and there are restrictions in place for pick-up and drop-off traffic.

The majority of flights are leaving on time.

The forecourt at Inverness Airport is closed to drop-off and pick-up traffic.

There are no reports of any delayed or cancelled flights.

Steel bollards are to be installed at all subway and bus stations in Glasgow to protect the buildings from attacks by car.

Security patrols on underground trains and platforms are being increased and CCTV footage is being monitored more closely.

British Transport Police said police patrols were being stepped up across the rail network and random searches on vehicles approaching stations and passengers were being increased.

There are no delays to SPT or First ScotRail services.

Concrete blocks have been installed in front of the NorthLink terminal building at Aberdeen Harbour.

Passengers can still be dropped off in front of the terminal, but cars are not allowed to wait.

The left luggage facility at Aberdeen has also been suspended.

Parking near the Calmac ferry terminals at Gourock, Ardrossan and Oban has been restricted to staff and cars with valid disabled badges.

More vehicle inspections are being carried out on Calmac services and customers are being advised allow extra time for their journey.

Passengers are also being asked to phone ahead to check for delays and cancellations.