A British lawmaker in Prime Minister Boris Johnson's Conservative Party was stabbed to death by a man who walked into a meeting with voters from his electoral district, police said.
Attacks on individual lawmakers in Britain are rare, but the nature of their work can leave them exposed in face-to-face encounters with strangers.
In Westminster, where lawmakers do much of their work in Parliament, armed police patrol the entrances, corridors and halls. In their home electoral districts, known as constituencies, more often than not there is no security.
Lawmaker David Amess was stabbed while holding a surgery -- a one-to-one meeting with voters much like when a patient consults a doctor. They are a chance for lawmakers to meet, listen to and advise the people who elected them, in an informal atmosphere.
Here are some more lawmakers who have been attacked while at -- or going to -- constituency surgeries.
Jo Cox, 2016
Opposition Labour party lawmaker Jo Cox was shot dead in the street the week before Britain's vote on whether to leave the European Union. A vocal supporter of Britain remaining in the EU, she was attacked while preparing to meet constituents in her electoral district.
Thomas Mair, 53, a loner obsessed with Nazis and extreme right-wing ideology, shot and stabbed the 41-year-old mother of two, shouting "Britain first" during the attack and later giving his name in court as "death to traitors, freedom for Britain."
He was sentenced to life in prison in November 2016.
Stephen Timms, 2010
Labour member and ex-cabinet minister Stephen Timms was stabbed in the stomach at his office in east London during a constituency meeting by a 21-year-old student who was angry over his backing for the 2003 Iraq war.
He survived the attack after emergency surgery, and is still a lawmaker. His attacker was sentenced to life in prison with a minimum of 15 years.
Nigel Jones, 2000
In 2000, a Liberal Democrat local councilor was murdered by a man with a samurai sword at the offices in western England of lawmaker Nigel Jones, who was also seriously hurt in the attack.