Three police forces in England have used a new law for the first time to stop and search terrorism suspects, the Home Office has revealed.
Police only started using the new powers in the aftermath of the Parsons Green Tube attack on 15 September.
In September, British Transport Police (BTP) carried out 126 stop and searches whilst the North Yorkshire and West Yorkshire forces each conducted one.
Following the searches four people were arrested by BTP.
A fourth force, the City of London police was also authorised to use the new powers but carried out no searches.
The new powers are contained under Section 47a of the Terrorism Act, which allows police forces to stop and search suspects when they have reasonable suspicion an act of terrorism will take place.
The law was created in 2011 after the European Court of Human Rights ruled that the previous terrorism stop and search powers, used by the police, contravened the European Convention on Human Rights.
It was not until after the Parsons Green Underground attack in September, which saw an improvised explosive device injure 29 people, that police forces decided to use the new powers.
In the aftermath of the attack the government raised the terrorism threat level to critical, meaning an attack was expected imminently.
West Yorkshire Police said it used section 47a to stop a 33-year-old man it received reports of an individual taking images near a shopping centre.
Assistant Chief Constable Russ Foster said the new powers "provide police with an essential tool to prevent and detect acts of terrorism, gather intelligence and make our communities safer".
"It demonstrates the level of vigilance we continue to apply across our towns and cities and we would urge members of the public to remain alert, but not alarmed", he said.
The latest figures from the Home Office show a record number terror-related arrests were made in the UK in the year to September, with 400 people being detained.
Security Minister Ben Wallace said police and security services "have been clear that we are facing a shift rather than a short-term spike in the terrorist threat".
"The statistics we are publishing today demonstrate the breadth of work that they undertake, alongside the rest of the criminal justice system, day in and day out to keep us safe. "But this is not the totality of our work.
"The whole of society must come together to challenge the terrorist threat.", he added.