LONDON >> Dramatic video footage released today captures the moment when armed police swooped into a busy market area near London Bridge on Saturday night and shot dead three attackers who had just left a trail of bloodshed, killing eight people and wounding scores.

The surveillance camera footage shows the first police car rolling forward as the attackers lunge at a man to stab him during the late night attacks. Within minutes, the attackers are shot dead and another police car arrives as people are seen running for their lives.

During the confrontation, passers-by can be seen throwing objects at the attackers before the last victim is shown stumbling away. Shortly later, the lifeless bodies of the attackers are seen on the pavement. Some 48 rounds were fired to stop the attack within eight minutes.

The family of 32-year-old James McMullen, who was killed in the rampage, issued a statement calling the attackers “deranged and deluded individuals.”

His family said: “While our pain will never diminish it is important for all of us to carry on with our lives in direct opposition to those who would try to destroy us.”

The family of an off-duty police officer, Charlie Guenigault, who has been hailed as a hero for running toward the attackers, praised his bravery and said he would likely do the same again if faced with the same situation. Police said 25-year-old Guenigault is in a hospital in stable condition.

As investigators hunted for potential accomplices linked to the three attackers today, voters cast ballots in a British general election that has spotlighted security concerns.

Police briefly closed off an area of London near the busy Charing Cross train station after a suspicious package was found. The Metropolitan Police said the package was not terror-related. Security patrols have been boosted throughout London.

Saturday’s attack was the third such deadly incident in England in just three months.

Police arrested three men in east London Wednesday over the attack, taking them to police stations for questioning. A total of five people are in custody, though none has been charged.

One of those arrested is a man who allegedly worked out at the same gym as 27-year-old Khurum Butt, thought to be the attack ringleader. The two other attackers were named as 22-year-old Youssef Zaghba and 30-year-old Rachid Redouane.

Butt, once seen in a documentary called “The Jihadis Next Door,” had been repeatedly reported to police for his violent behavior and reports from a neighbor who said he was trying to lure young kids to radical Islam. His name had also been flagged in 2015 by F.B.I. informant Jesse Morton who told authorities he had met Butt in an extremist internet chatroom used by Anjem Choudary, one of Europe’s most prolific hate preachers who was jailed last year for his support of the Islamic State group, according to a British government official who spoke on condition of anonymity because he was not authorized to speak about the ongoing attack investigation.

Born in Pakistan, Butt’s family in Britain released a statement on Wednesday apologizing for his actions. Relatives in Pakistan, meanwhile, said he had brought shame on to the family.

The Italian mother of Zaghba, whose father was Moroccan, said Wednesday that her son had become radicalized in Britain after falling in with the wrong group of friends. Italian authorities alerted their British counterparts after he bought a one-way ticket to Turkey. He had said he wanted to go to Syria to start a family, according to his mother.

Redouane, a Moroccan pastry chef who had married a British woman and lived in Ireland for some time, was the only one of the three attackers who had not come onto British security’s radar.

London’s Borough Market remained sealed off today with only a scattering of businesses opening nearby. The market was unlikely to open before Sunday, according to police.

One of the businesses to re-open was a branch of fast-food chain Leon. On the night of the attack, staff pretended to lock the doors in a move that was thought to protect 20 customers inside. One customer outside the shop was stabbed several times in the neck.

“Some of the people who were here on Saturday night are still a bit fragile,” said Leon chief executive John Vincent. “Some people who weren’t here on Saturday night have got this whole guilt thing going on that they weren’t here to be supportive to their colleagues.”

Britain’s counter-terror chiefs said they are launching a major drive to train festival workers in the wake of the three deadly attacks.

The measures were announced as the summer music season gets into full swing. The Glastonbury music and arts festival, which is expected to draw 150,000 people to a farm in southwest England to see acts including Radiohead, Foo Fighters and Ed Sheeran, takes place later this month.