The UK's senior counter terrorism police officer has questioned the value of stop-and-search powers.
Mr Hayman questioned the "price" of the powers
Andy Hayman, the Metropolitan Police's assistant commissioner responsible for anti-terror probes, said few arrests or charges arose from such searches.
"It is very unlikely that a terrorist is going to be carrying bomb-making equipment around... in the street," he told a London police authority hearing.
It was "a big price to pay" given some people feel unfairly targeted, he said.
Mr Hayman gave his assessment at a hearing for the Metropolitan Police Authority's inquiry Counter Terrorism: The London Debate.
He told it: "It is very unlikely that a terrorist is going to be carrying bomb-making equipment around with them in the street.
"So, I am not sure what purpose it serves, especially as it upsets so many people, with some sections of our community feeling unfairly targeted.
"It seems a big price to pay."
The powers come under Section 44 of the Terrorism Act 2000.
Mr Hayman said the powers were well intended, "to try and prevent, deter and disrupt terrorist activity".
He added: "But we have to question the way we use a power that causes so much pain to the community we serve but results in so few arrests or charges. Is it worth it?"
Asked later about the comments, released by the Metropolitan Police Authority, the Metropolitan Police said it acknowledged the impact that the use of Section 44 powers can have in certain communities.
"This is why it is important that these issues are debated in a frank and open way, that the public's concerns are recognised and taken account of and that the powers themselves are used in a focused and balanced way," the statement said.
At the same hearing the Home Office's director of counter-terrorism and intelligence, William Nye, said the government constantly assessed whether the counter-terrorism measures struck the right balance between liberty, equality and security.
"We need to listen to what people are saying about this power and listen also to the police on how useful it is and the impact it has on our communities," he said.
The police authority's report at the end of the inquiry is expected to be published in February.
In a press statement, Toby Harris, MPA member with special responsibilities for counter-terrorism, said: "The very clear message from Londoners through the MPA counter-terrorism hearings has been that there is real unease over the disproportionate and inconsistent use of this power."