PEOPLE in Dorset are being reminded to be alert to the danger of terrorism in the aftermath of the Westminster terror attack.

It comes as the Islamic State terror group claims that the Westminster attacker, who was shot dead by police, was one of its "soldiers".

A minute's silence was held nationwide today at 9.33am, including in the Palace of Westminster and at New Scotland Yard, to commemorate the three innocent people who were killed.

The timing of the silence was chosen in honour of the shoulder number of the policeman PC Keith Palmer who died after being stabbed in the attack.

The Prime Minister has also praised the "extraordinary" bravery of Dorset MP Tobias Ellwood, as calls grew for him to be given an honour after he battled to save the life of PC Palmer.

Mr Ellwood, a Conservative Foreign Office Minister, ran towards the gunfire to help PC Palmer.

He tried to give the officer mouth-to-mouth resuscitation and stem the blood amid the carnage in New Palace Yard, but the officer died from his injuries.

Meanwhile, in a statement released by Dorset Police today, Chief Superintendent Colin Searle said: “Our thoughts are with anyone affected by yesterday’s events in London and our condolences are with the families and friends of those who tragically lost their lives, including a serving police officer.

“Public safety is our priority and we have a variety of established operational tactics that are regularly used to ensure that our local communities and businesses are both well prepared and protected.

“Our aim is to reduce the risk to the public and maximise public awareness. As is normal practice, we are in touch with national anti-terrorism coordinators.

“There has been no change to the threat level in the UK. We regularly review intelligence and information and would like to reassure the public that there is no specific threat to Dorset. The public should be alert but not alarmed.

“The advice remains the same – members of the public should always remain alert to the danger of terrorism and report any suspicious activity to police on 999 or the anti-terrorist hotline 0800 789 321.”

The Westminster attacker was a British citizen who was known to the police and security services, and had been investigated some years ago over violent extremism.

Prime Minister Theresa May told MPs he was a "peripheral" figure, adding: "He was not part of the current intelligence picture."

Delivering a defiant message to a packed House of Commons this morning, Mrs May said: "We will never waver in the face of terrorism."

A statement released through IS's Aamaq news agency said the attacker was a "soldier of the Islamic State".

According to the SITE Intel Group, which monitors jihadist groups, the IS statement said: "The attacker yesterday in front of the British Parliament in London was a soldier of the Islamic State executing the operation in response to calls to target citizens of coalition nations."

The Prime Minister addressed MPs as they gathered at the usual time inside the Palace of Westminster, which a day earlier had come under attack from the knife-wielding terrorist.

An hour after MPs had stood for a minute's silence in honour of the innocent people killed in the attack, Mrs May delivered a statement with details of the atrocity.

Paying tribute to PC Keith Palmer, she said: "He was every inch a hero and his actions will never be forgotten."

Describing the terrorist, Mrs May said: "What I can confirm is that the man was British-born and that some years ago he was once investigated by MI5 in relation to concerns about violent extremism. He was a peripheral figure.

"The case is historic. He was not part of the current intelligence picture. There was no prior intelligence of his intent or of the plot."

Anti-terror police have arrested eight people in the wake of the attack.

Several addresses were raided overnight in London and Birmingham as Mark Rowley, the Metropolitan Police's senior anti-terror officer, said he believed the attacker was working alone.

Aysha Frade was the first member of the public to be identified as a victim, with her principal at DLD College London describing her as "highly regarded and loved".

Forty other people were injured in the attack, with 29 treated in hospital, where seven remained in a critical condition on Thursday.

The casualties included 12 Britons, three French children, two Romanians, four South Koreans, two Greeks, and one each from Germany, Poland, Ireland, China, Italy and the United States. Three police officers were also hurt, two of them seriously.