London Bridge stabbing: 2 killed in attack by convicted terrorist released in 2018

LONDON -- Two people were killed and three others hospitalized after they were stabbed in a terror attack near the London Bridge Friday afternoon, authorities said.

The lone male suspect was shot by police and died at the scene, according to authorities, who added that a device believed to be a hoax explosive was strapped to the suspect.

He's since been identified as Usman Khan, 28, a convicted terrorist who was released in 2018, according to Neil Basu, assistant commissioner for the Metropolitan Police.

Khan "had been residing in the Staffordshire area. As a result, officers are, tonight, carrying out searches at an address in Staffordshire," Basu said in a statement. "This individual was known to authorities, having been convicted in 2012 for terrorism offences. He was released from prison in December 2018 on licence and clearly, a key line of enquiry now is to establish how he came to carry out this attack."

Authorities "are not actively seeking anyone else in relation to the attack," Basu added. "However, we continue to make fast time enquiries to ensure that no other people were involved in this attack and that there is no outstanding threat to the public."

It was reported earlier that the suspect had been linked to terror groups and, according to U.S. law enforcement officials briefed on the incident, was a recently released terrorist wearing an electronic tag.

Police were called to the scene at 1:58 p.m. local time. The suspect was confronted five minutes later, police said.

Tor Caldwell and Patrick Brown, who were on a bus on the bridge at the time of the attack, "saw some commotion out the side of the bus" and heard gunshots, Brown told ABC News.

"People on the street were running," Caldwell said.

A police officer evacuated the bus passengers and told them to run, Caldwell said.

"It was pretty scary because we didn't know what was going on," Brown said.

Authorities still are working to determine a motive and if any other suspects were involved, Metropolitan Police Commissioner Cressida Dick said.

At a news conference, Dick thanked "the members of the public who have helped, either by showing extraordinary courage by stepping in or by following the instructions they’ve been given by officers at the scene and in the area."

"This support from our public assists us more than you could know," she said.

London's Metropolitan Police Service said it's "enhancing police patrols" in the city in the wake of the attack.

"We urge the public to remain calm, but be alert and vigilant," police officials tweeted.

Prime Minister Boris Johnson called the attack "appalling," tweeting, "All my thoughts are with the victims and their families."

Johnson told reporters, "I can assure you that anyone involved in this attack will be hunted down and brought to justice."

London Mayor Sadiq Khan said the city would "stay resolute in our determination to stand strong and united in the face of terror."

In June 2017, eight were killed when a group of attackers plowed a van into people on London Bridge and then drove to nearby Borough Market and stabbed several others.

ABC News' Rashid Haddou, Josh Margolin and Matt Foster contributed to this report.