The Government has issued travel advice to anyone planing to travel to Belgium after explosions at Brussels airport and the city's metro system.
23 people are reported to have been confirmed dead so far what is believed to be a series of attacks.
Here is the Government's official advice:
The Belgian government has placed the whole of Belgium at threat level 3 – a possible and real threat. You should remain alert and vigilant, especially in places where there’s a high concentration of people. Follow the advice of local authorities and respect security controls. You can find more information on the Belgian Crisis Centre website and Twitter feed.
There have been a number of police raids and arrests in the Brussels region and other Belgian cities in recent weeks. Belgian security operations are likely to be carried out at short notice. If you’re in an affected area you should follow the instructions of the Belgian security authorities.
Police have asked the public not to comment on police operations on social media. Police operations are likely to continue in Forest and Brussels; you should follow the instructions of the local authorities.
Public events and busy public areas across Belgium are likely to see additional security. Some public events may be cancelled and some tourist attractions closed. Contact event organisers for information on whether specific events are going ahead. You should check this travel advice for updates and subscribe to email alerts.
How safe is it and what should I do if I need help in Belgium?
Up to 1.8 million British nationals visit Belgium every year. Most visits are trouble-free. Take out travel and medical insurance before you travel.
If you need to contact the emergency services in Belgium call 112.
First World War commemorations
7) If you’re travelling to commemorate the First World War , see this information and advice page to help plan your trip and make sure it’s safe and trouble free. Some sites will become extremely busy at certain times of the year, and some may have access restrictions.
When visiting former WW1 battlefields in north west Belgium, stay on the footpath and exercise caution if you see anything that looks like shells or munitions. Unexploded shells have recently been uncovered. Move away from the site and call the police emergency number 112 to report any incidents.
Travel and crime
European summits and demonstrations often take place around the Schuman area. They can cause some disruption and access to the British Embassy and the British Consulate General can be affected. Check local news and transport sites: train & metro info and also road info.
Theft and pick pocketing is a problem in crowded areas. Take care of your belongings and passports at all train stations in Brussels. Read crime advice for Brussels here
The Overseas Business Risk service offers information and advice for British companies operating overseas on how to manage political, economic, and business security-related risks.