Armed police officers have been spotted patrolling Kent today following the deadly terrorist attack in Manchester.

Prime Minister Theresa May announced last night that the decision has been made to increase the national threat level to 'critical' - the highest level.

The announcement comes following a terror attack at an Ariana Grande concert at Manchester Arena on Monday night, which has so far left 22 people, including children, dead.

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Kent Police has now confirmed patrols will be stepped up - but soldiers will not be brought in just yet.

A spokesman said the force is liaising with the Home Office to regularly assess the national threat levels and what that means for communities.

The work is part of a national plan, which includes the possibility of bringing in the military to support police officers.

VIDEO: Officers armed with guns have been seen in Ashford.

Police officials in Kent have confirmed they have not requested the support of the Armed Forces.

Kent Police already has firearms officers at key locations in the county, including Bluewater, Dover Docks and Canterbury Cathedral, but additional patrols are being arranged.

Armed officers have been spotted on patrol in Ashford, Maidstone and Gravesend today.

A police statement said: "Our sympathies remain with those affected by the events in Manchester but we ask people to continue to enjoy our county and stay alert, not alarmed.

"This threat level applies to the whole of the UK and not any specific area.

"As such, the whole UK public should remain alert and vigilant and report anything suspicious by calling the Anti Terrorist Hotline 0800 789 321."

Watch: Kent Police have stepped up patrols in the county

Eurostar also responded to a request for a comment on security at their stations, including Ashford International.

A spokesman said: "We already operate at the highest level, in line with the policy set by the relevant authorities in the countries that we operate in.

"We take the safety and security of our passengers very seriously and operate with the strictest security regime of any train operator.

"These security requirements are defined and regularly audited by the relevant authorities in each country that we operate in and are comparable to those undertaken at airports."