The man who killed two Jewish men outside a synagogue on the holiest day of the religion's calendar was a British citizen of Syrian descent, police have said.
Three people have been arrested on suspicion of planning a terror attack in connection with the killings carried out by Jihad Al-Shamie, Greater Manchester Police added.
Jihad Al-Shamie, 35, was shot dead by police seven minutes after officers were alerted to the attack this morning.
The police force said two men in their 30s and a woman in her 60s were arrested on suspicion of the commission, preparation and instigation of acts of terrorism.
It is understood that Jihad Al-Shamie's name has not appeared in initial searches of police and security service records, and he is not thought to have been under investigation.
Two men died in the attack and three men remain in hospital with serious injuries after Al-Shamie - who is yet to be formally identified - rammed into people with a car before stabbing a man outside the Heaton Park Hebrew Congregation Synagogue in Crumpsall, Greater Manchester, on Thursday morning.
Among the men in hospital, one was stabbed and a second was hit by the car.
A third man "presented himself at hospital with an injury that may have been sustained as officers stopped the attacker", police said.
A bomb disposal unit was called to the scene this morning, with a loud controlled explosion having been carried out, Greater Manchester Police (GMP) has said.
GMP said officers had been called to Heaton Park Hebrew Congregation Synagogue in the north Manchester district of Crumpsall after a witness said they had seen a car driven at members of the public and that one man, believed to be a security guard, had been stabbed.
The attacker, who was wearing a vest which looked like an explosive device, was shot dead within seven minutes of the initial call to police.
UK Prime Minister Keir Starmer visited a synagogue this evening after he vowed to do "everything in my power" to protect Jewish communities in the UK.
In a statement, the Board of Deputies and the Jewish Leadership Council said the attack was "something we feared was coming" because of "rising anti-Semitism in the UK".
Officials hailed those inside the synagogue who barricaded the door and prevented the attacker from getting inside.
GMP Chief Constable Stephen Watson praised the "immediate bravery" of security staff and worshippers who shut the attacker out during what Greater Manchester mayor Andy Burnham described as a "horrific anti-Semitic attack".
Mr Watson said: "There were a large number of worshippers attending the synagogue at the time of this attack, but thanks to the immediate bravery of security staff and the worshippers inside, as well as the fast response of the police, the attacker was prevented from gaining access."
Police said earlier it had "declared Plato" - the national code-word used by police and emergency services when responding to a "marauding terror attack".
In a statement, the force said: "Police were called to the Heaton Park Hebrew Congregation Synagogue, on Middleton Road, Crumpsall, at 9.31am by a member of the public, stating he had witnessed a car being driven towards members of the public and one man had been stabbed."
A video shared on social media and verified by Reuters showed police shooting a man inside the synagogue's perimeter, while another man lay on the floor in a pool of blood, appearing to wear a traditional Jewish head covering.
The police force said it declared a major incident at 9.37am this morning.
The force confirmed the suspect's death a few hours after shots were fired by armed police at 9.38am.
After the attack, the force said a loud explosion could be heard as "specialist resources gained entry to the suspect’s vehicle as a precaution".
The attack comes as members of the Jewish community observe Yom Kippur - considered the holiest day in the Jewish calendar and a time when synagogues are usually particularly busy.
Starmer commits to guaranteeing safety of Jews in Britain
UK Prime Minister Sir Keir Starmer said he was "appalled" at the attack adding: "The fact that this has taken place on Yom Kippur, the holiest day in the Jewish calendar, makes it all the more horrific."
Speaking from Downing Street after a Cobra emergency committee meeting, Mr Starmer condemned the "terrorist attack that attacked Jews because they are Jews", which he said had been committed by "a vile individual".
Addressing the Jewish community in the UK, he said: "I promise you that I will do everything in my power to guarantee you the security that you deserve, starting with a more visible police presence, protecting your community.
"I promise you that over the coming days, you will see the other Britain, the Britain of compassion, of decency, of love.
"And I promise you that this Britain will come together to wrap our arms around your community and show you that Britain is a place where you and your family are safe, secure and belong."
President Michael D Higgins said "all those who value life will be appalled at the horrific attack".
"I join with all those who have condemned this attack on the Jewish community in Britain, a community that has a proud tradition in the history of human rights.
"May I express my condolences to the relatives of those who have been killed and to other members of the Jewish community, and wish a speedy recovery to those who have been injured," President Higgins said.
Tánaiste Simon Harris expressed his "deepest condolences and solidarity with all those affected by the horrific attack today on the Heaton Park Hebrew Congregation Synagogue in Manchester".
"This appalling act is all the more repugnant given that it took place on Yom Kippur, the holiest day in the Jewish calendar.
"Our thoughts are also with the first responders and emergency services, as well as the wider community in Manchester, as they deal with this shocking event," Mr Harris said.
"I will be in touch with my colleagues in the UK Government to express our deepest sympathies and support."
Home Secretary 'horrified by news of attack'
In a statement posted on X, UK Home Secretary Shabana Mahmood said: "I am horrified by the news of an attack at a synagogue in Manchester today, on the holiest day in the Jewish calendar.
"My first thoughts are with the victims, our brave police and emergency services.
"I am being kept updated by Greater Manchester Police. I urge people to follow the advice of the emergency services."
The Israeli embassy in London condemned the attack, calling the act which left two people dead "abhorrent and deeply distressing" in a social media post.
Dave Rich, of the Community Security Trust (CST) - a charity that monitors anti-Semitism in the UK, said Yom Kippur is similar to Christmas Day for Christians, but is a day of solemnity and fasting rather than celebration.
He said: "Yom Kippur is the holiest day of the Jewish year.
"It's a very solemn day and synagogues across the country will be full throughout the day.
"There's always a significant security operation in place between police and CST across the Jewish community on all major Jewish festivals."
King Charles said he and the queen were "deeply shocked and saddened to learn of the horrific attack in Manchester, especially on such a significant day for the Jewish community".
Additional reporting by Reuters
