London police on Monday named two of the three attackers who killed seven people near London Bridge late on Saturday and injured dozens more.
The Metropolitan Police said one attacker was Khuram Shazad Butt, aged 27.
Butt, a British citizen born in Pakistan, was already known to police and Britain's domestic spy agency MI5, the police said.
The second attacker was named as 30-year-old Rachid Redouane, who police said claimed to be Moroccan and Libyan. He also went by the name Rachid Elkhdar with a different date of birth.
Both men lived in the same area of east London.
"However, there was no intelligence to suggest that this attack was being planned and the investigation had been prioritised accordingly," police said.
Police said they were still working to establish the identity of the third attacker.
Late on Saturday the three attackers drove south across London Bridge, mowing down pedestrians before stabbing bystanders in the nearby Borough Market area.
The attacks, that came came less than a week before parliamentary election, left seven dead, including foreign nationals, and dozens injured, 18 in a critical condition.
British police are stretched by the number of people they believe could potentially commit an act of terrorism.
There are 500 current investigations involving 3,000 potential suspects.
TRT World's Sarah Morice has more from London.
"We're all Londoners"
Crowds gathered by London's beloved Tower Bridge on Monday — many Muslims among them — to grieve for the victims of the city's second attack in three months.
Mourners held up signs such as "Love for all, hatred for none" and "N.Ireland supports London," as the British flag flew at half-mast on the bridge, a monument of national endurance.
In a brief speech at the vigil, London Mayor Sadiq Khan seemed to speak for many as he voiced his sorrow and anger.
"London stands in defiance," said Khan.
To applause and cheers, Khan described himself as "a proud and patriotic British Muslim" and coldly slapped down those who invoked Islam to justify acts of murder.
Sniffer dogs roamed the area before the brief vigil, and police, armed and unarmed, maintained a high-profile presence.
French citizens missing
Two French citizens have been missing since Saturday night's attack in London, Foreign Minister Jean-Yves Le Drian said on Monday during a visit to the French embassy in the British capital.
Le Drian confirmed that one French citizen died in the attack and said eight French had been injured, four of whom are in a serious condition.
The four others suffered less serious injuries and two of them are not in hospital anymore, he told reporters.
The threat level remains at 'severe' in UK where, according to authorities, increased security measures are being put in place.
TRT World's Francis Collings reports from London.