Terrifying video captured the moment police shot dead a man wearing a fake suicide vest after a group of heroic bystanders tackled the knife-wielding suspect, who had just stabbed several people — killing at least two — on London Bridge in what was described as a terrorism incident, according to officials and reports.

The officers opened fire on the suspect moments after he was wrestled to the ground by bystanders, according to The Sun.

In the dramatic video, a good Samaritan also is seen running away from the deadly scene gingerly carrying a knife.

The heavily armed cops responded about 2 p.m. to reports of a “stabbing at premises near to London Bridge,” which links the city’s business district with the south bank of the River Thames.

But before the submachine gun-toting cops arrived, the brave passers-by had already wrestled the fleeing madman to the ground – a scene captured in chilling footage shot by various people from different vantage points at the chaotic scene.

One video posted on social media showed two men fighting on the bridge before officers pulled a man in civilian clothes off a black-clad man on the ground. Shots then rang out.

Other images showed police — guns drawn — pointing at a person on the ground in the same area where eight people were killed and 48 others injured in a vehicle-ramming and stabbings by Islamic militants along the iconic bridge on June 3, 2017.

“A male suspect was shot by specialist armed officers from the City of London police and I can confirm that this suspect died at the scene,” Neil Basu, the UK’s top counter-terrorism officer, told reporters.

“A number of other people received injuries during this incident. We believe a device that was strapped to the body of the suspect was a hoax explosive device,” he said, adding that authorities were keeping an “open mind as to any motive.”

The identities and conditions of the injured were not immediately known.

Mayor Sadiq Khan praised the Londoners who tackled and disarmed the attacker.

“What’s remarkable about the images we’ve seen is the breath-taking heroism of members of the public who literally ran towards danger not knowing what confronted them,” Khan told reporters.

“Members of the public didn’t realize at the time that was a hoax device, and they really are the best of us,” he said, adding that police were not looking for anyone else in the incident.

The White House condemned the attack and pledged “full support to our ally, the United Kingdom,” spokesman Judd Deere said.

“President Trump has been briefed on this morning’s attack at the London Bridge and is monitoring the situation,” Deere said in a written statement. “The United States strongly condemns all horrific acts of violence on innocent people.”

Amanda Hunter, who was on a bus on the bridge at the time of the attack, described the deadly incident.

“All of a sudden [it] stopped and there was some commotion and I looked out the window and I just saw these three police officers going over to a man,” she told the BBC.

“It seemed like there was something in his hand, I’m not 100 percent sure. But then one of the police officers shot him,” she added.

Noa Bodner, who was stuck in a restaurant near the scene, told the BBC that “there was a rush of people coming in and everybody basically dived under the tables.

“We were told to keep away from the windows, people that came from the outside were saying that shots were fired,” she said, adding that the manager ran to lock the doors and staff told people to move away from the front of the eatery.

Aditi, 29, a visitor from New York, went into hiding in the attic of a cheese shop, according to The Guardian.

“A policeman came to the crowd near Kappacasein Dairy and asked us to move indoors but at the time we couldn’t process that information or know what to do with it,” said Aditi.

“I then noticed people starting to run very fast away from the entrance of Borough Market, so we ran down a side street and noticed people running into Neal’s Yard Dairy,” Aditi continued.

“We were one of the last to get in before they locked the door. We were taken to the attic and the staff said they had been trained for such an incident. We were there for around 30 minutes before the police gave clearance to exit and move further away from the market. My partner and I are rattled but OK. We’re just glad to be safe.”

Prime Minister Boris Johnson was on his way back to Downing Street and Basu said he would be giving him a full briefing.

“I’m being kept updated on the incident at London Bridge and want to thank the police and all emergency services for their immediate response,” Johnson said in a statement.

With Post wires