"The increase in the threat level is related to developments in Syria and Iraq where terrorist groups are planning attacks against the west. Some of those plots are likely to involve foreign fighters who have travelled there from the UK and Europe to take part in those conflicts.

"The first and most important duty of government is the protection of the British people. We have already taken steps to improve our powers and increase our capabilities for dealing with the developing terrorist threats we face. That process will continue and the British public should be in no doubt that we will take the strongest possible action to protect our national security.

"We face a real and serious threat in the UK from international terrorism. I would urge the public to remain vigilant and to report any suspicious activity to the police."

The UK is faced with potential terror-related attacks due to its activity in other parts of the world and for no other reason.

It is highly inconsiderate and in fact downright wrong for the UK government to lead people into fear without fully explaining the reasons in full.

There are five levels of threat used by the JTAC. These are:
• Critical - an attack is expected imminently
• Severe - an attack is highly likely
• Substantial - an attack is a strong possibility
• Moderate - an attack is possible but not likely
• Low - an attack is unlikely