The Maltese investigative journalist and blogger who led the investigation into the Panama Papers scandal has been killed by a car bomb.
Daphne Caruana Galizia, 53, died on Monday when a powerful explosive device blew up her car, police said.
Ms Caruana Galizia ran a hugely popular blog in which she relentlessly highlighted cases of alleged high-level corruption targeting politicians across party lines.
In a post published on her site just half an hour before the explosion she wrote: "There are crooks everywhere - the situation is desperate."
Locals said Ms Caruana Galizia had just left her house and was on a road near the village of Bidnija in northern Malta when the bomb detonated, sending her car flying into an adjacent field.
Malta's prime minister, Joseph Muscat, who faced accusations of wrongdoing by Ms Caruana Galizia earlier this year, denounced her killing, calling it a "barbaric attack on press freedom".
Listen to April 2016 interview with Daphne Caruana Galizia on Nine to Noon
Mr Muscat announced that the US Federal Bureau of Investigation had agreed to help local police investigate the killing and was flying experts to the island as soon as possible.
"I will not rest until I see justice done in this case," he said in a statement, calling for national unity.
Malta has a population of 400,000 and is the European Union's smallest state.
"Everyone knows Caruana Galizia was a harsh critic of mine, both politically and personally, but nobody can justify this barbaric act in any way," Mr Muscat said. "The only remedy for anyone who felt slandered was through the courts." Mr Muscat sued Caruana Galizia over blogs she wrote earlier this year.
"She was adored and resented in equal measure ... she was a no holds barred kind of writer" - Maltese journalist Herman Grech
Looking for a vote of confidence to counter allegations against him, Mr Muscat called snap elections in June which he easily won. Recently, Ms Caruana Galizia's outspoken blog had turned its fire on opposition politicians.
Malta Television reported that Ms Caruana Galizia had filed a complaint to the police two weeks ago to say she had received threats. It gave no further information.
Opposition leader Adrian Delia said the blogger was the victim of a "political murder".
"Caruana Galizia revealed the Panama Papers and was the government's strongest critic," he said, calling for a independent probe of her killing.
"We will not accept an investigation by the Commissioner of Police, the Army commander or the duty magistrate, all of whom were at the heart of criticism by Caruana Galizia," he said.
European politicians expressed dismay at her death.
"A dark day for democracy," tweeted Manfred Weber, head of the conservative bloc in the European Parliament.
Ms Caruana Galizia took aim at politicians and senior officials from across Malta, seeing the island as a hotbed of corruption.
"Malta's public life is afflicted with dangerously unstable men with no principles or scruples," she wrote last year.