The two "terrorist incidents" at London Bridge and Borough Market on Saturday night are among several attacks that have taken place in the United Kingdom in recent years.
Here is a timeline of recent attacks.
May 22, 2017
Twenty-two people -- including children -- are killed and around 59 injured during a suspected terrorist bombing at a pop concert in Manchester.
Lone suicide bomber Salman Abedi detonated an improvised explosive device as crowds of music fans, many of them youngsters, left Manchester Arena following a performance by US artist Ariana Grande.
March 22, 2017
Five people are killed when a man launched a car and knife attack in central London. Khalid Masood drove a hire car over Westminster Bridge, near the Houses of Parliament, mounted the pavement and hit pedestrians before crashing into railings outside the Palace of Westminster.
He stabbed Police Constable Keith Palmer, 48, to death and also killed US tourist Kurt Cochran, Romanian tourist Andreea Cristea, 31, and Britons Aysha Frade, 44, and 75-year-old Leslie Rhodes. Masood was shot dead by police.
June 16, 2016
Labour MP Jo Cox is murdered outside her constituency office in Batley, West Yorkshire. The mother of two (41) was shot and stabbed multiple times by right-wing extremist Thomas Mair. He was later handed a whole-life prison sentence for her murder.
December 5, 2015
A lone attacker attempts to behead a passenger during an Islamic State-inspired rampage in the ticket hall of Leytonstone Underground station in east London. Somali-born Muhiddin Mire targeted strangers at random during the attack before slashing fellow passenger Lyle Zimmerman, 56, with a knife. The schizophrenic was sent to Broadmoor Hospital after being given a life sentence with a minimum term of eight years for attempted murder.
May 22, 2013
Fusilier Lee Rigby is murdered by Islamic extremists Michael Adebolajo and Michael Adebowale.
The 25-year-old serviceman was walking near his barracks in Woolwich, south-east London, when the pair rammed him with a car before attempting to hack off his head with knives. The killers were jailed for life at the Old Bailey in February 2014.
July 7, 2005
Four suicide bombers kill 52 and injure hundreds of others in blasts on the London Underground network and a bus.
Twenty-six died in the bombing at Russell Square on the Piccadilly line, six in the bombing at Edgware Road on the Circle line, seven in the bombing at Aldgate on the Circle line, and 13 in the bombing on a bus at Tavistock Square.