By Emanuella Grinberg, Ben Westcott and Angela Dewan

LONDON (CBS/CNN) — Authorities have named the man they believe is behind the terror attack in London yesterday.

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Scotland Yard names 52-year-old Khalid Masood as the alleged suspect.

A veteran policeman and a teacher were among those killed in the terror attack that struck at the heart of the British capital.

Keith Palmer, a 48-year-old father and husband, had served as an officer for 15 years. He was on duty, unarmed, at the gates of Parliament when a man stabbed him to death.

Local British Nationals Reeling Following London Terror Attack

“He was someone who left for work today expecting to return home at the end of his shift, and he had every right to expect that would happen,” Britain’s most senior counter-terrorism police officer Mark Rowley said.

Another victim has been identified as Aysha Frade, a 43-year-old teacher. The mayor of Betanzos in Spain, Ramon Garcia Vasquez, confirmed her death. She had lived in London for several years with her Portuguese husband, he said, but she had relatives in Betanzos.

“We are totally overwhelmed by the news and we send our condolences to the people in London,” Garcia Vasquez told CNN.

London police told The Associated Press that a 75-year-old victim in the bridge attack died Thursday.

President Donald Trump tweeted on Thursday that Kurt Cochran, an American, was also killed in the attack.

According to the Associated Press, Cochran and his wife, Melissa, were on the last day of a trip celebrating their 25th wedding anniversary.

Melissa remains hospitalized.

The assailant was shot dead by armed officers.

On Thursday, ISIS claimed responsibility for the attack, but the group offered no proof of its involvement.

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‘A lovely man’

After the police officer Palmer was stabbed, bystanders rushed to his aid. As he lay bleeding on the cobblestone street, Conservative MP Tobias Ellwood gave him mouth-to-mouth resuscitation, to no avail.

“Keith Palmer was killed while bravely doing his duty, protecting our city and the heart of our democracy from those who want to destroy our way of life,” London Mayor Sadiq Khan said.

“He personifies the brave men and women of our police and emergency services who work around the clock to keep us safe — tonight all Londoners are grateful to them.”

At Scotland Yard, headquarters of London’s police force, flags were flying at half-staff on Wednesday evening, in honor of Palmer and the other victims.

His death drew tributes from politicians including Conservative James Cleverly, who said he served with Palmer in the Royal Artillery before he became a “copper.”

“A lovely man, a friend. I’m heartbroken,” Cleverly said on Twitter.

Tourists struck

Around 40 other people were injured, police have said, among them are five South Korean sightseers, an Australian resident, three French students and a Chinese tourist.

A man and three women in their 50s and 60s from South Korea suffered fractures, while another woman in her 60s needed surgery after sustaining a serious head injury.

In Australia, Attorney General George Brandis told the Senate a female permanent resident from South Australia had been hospitalized after the attack.

The three French students were from Saint-Joseph school in Concarneau in western France, according to the French Foreign Ministry. They were on a school trip to London. There was no word on the extent of their injuries.

“(Foreign Minister) Jean-Marc Ayrault supports the families of our compatriots concerned in this difficult time,” the statement said.

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