Watford Council will be flying its flags at half mast on council buildings today as a mark of respect to those who died in last night's horrific terrorist attack in Manchester.

Mayor Dorothy Thornhill said the flags at the town hall would be lowered.

She said:"This is a tragedy and our thoughts are with the people of Manchester today.

"It’s hard to fathom such a cowardly attack and one that could have happened anywhere.

"We are now all having to plan in our town. 

"All our emergency services work with stakeholders to prepare for this happening here.

"I pray it never will but sadly we have to be prepared."

Twenty two people, including children, died in what police have now said was an attack by a suicide bomber at the Manchester Arena.

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Hertsmere Borough Council is also flying its flag at half mast at the offices in Borehamwood (below).

Watford Observer:

Another 59 people were injured in the explosion which happened at 10.33pm last night at a concert by American singer Ariana Grande.

Hertfordshire Police also confirmed none of its officers have been deployed to the north west.

More than 20,000 people, mainly young people and children, were at the event.

Police were called to reports of an explosion at the Manchester Arena at 10.33pm, shortly after US singer Ariana Grande had finished her performance.

Greater Manchester Police chief constable Ian Hopkins said: "This has been the most horrific incident we have had to face in Greater Manchester and one that we all hoped we would never see.

"Families and many young people were out to enjoy a concert at the Manchester Arena and have lost their lives.

"Our thoughts are with those 22 victims that we now know have died, the 59 people who have been injured and their loved ones.

"We continue to do all we can to support them."

Mr Hopkins said a "fast-moving investigation" had established the attack was conducted by one man, although detectives are working to establish if he was "was acting alone or as part of a network".

Police confirmed the suicide bomber died at the scene. 

Victims described being thrown by the blast that scattered nuts and bolts across the floor.

More than 240 calls were made to the emergency services, with responders including 60 ambulances flooding the area.

While more than 400 police officers were deployed as part of the operation, with a visible presence remaining on the streets of Manchester on Tuesday.

The dozens of victims injured in the attack are being treated at hospitals across Greater Manchester, and a hotline has been set up for those with concerns over loved ones who remain unaccounted for.

A large cordon remains in place around the arena and nearby Manchester Victoria Station, which was evacuated during the incident and remains closed, while forensic investigators gather evidence.

Anyone with concerns over loved ones can contact 0161 856 9400 or 0161 856 9900 for assistance.