Malta has been left in shock by the killing of its best-known investigative journalist.

Daphne Caruana Galizia, who was renowned for exposing corruption in Maltese politics, died when a bomb exploded in her car as she drove away from her home in Mosta.

Ms Caruana Galizia's son wrote on Facebook that he discovered his mother's body in pieces, and he alleged Malta's Prime Minister Joseph Muscat of being complicit in her killing by presiding over a "culture of impunity" in a "mafia state".

"My mother was assassinated because she stood between the rule of law and those who sought to violate it," Matthew Caruana Galizia said. "She was the only person doing so."

The killing near the village of Bidnija stunned the Mediterranean island.


Frans Sant, who was driving in the other direction at the time of the blast, said: "I saw a small explosion coming from the car and I panicked. A few seconds later, around three to four seconds, there was another, larger explosion.

"The car continued coming down the hill, skidding at high speed, full of fire. The car missed me by around 3m (10ft). I tried to help but the fire was too much and the car ended up in the field."

Image: The killing had shocked Malta and raised concerns over freedom of expression

Thousands attended a candlelit vigil for the slain journalist on Monday.

In a country of just 430,000 people, her blog could attract daily audiences of up to 400,000.

Ms Caruana Galizia's work took aim at corruption and cronyism, and included exposes on the offshore holdings of political figures as revealed in the leaked Panama Papers.

Politico listed her as one of 2017's 28 most influential Europeans: a "one woman Wikileaks, crusading against untransparency and corruption".

She had been sued by leading Maltese politicians - and in February, her bank was frozen after she reported that the leader of Malta's Labour Party had visited a brothel.

Image: Ms Caruana Galizia was facing lawsuits as a result of her work

Police have also confirmed she reported death threats two weeks before she was killed.

The European Commission expressed horror at the killing, and joined advocacy organisations in calling for a thorough investigation.

Pauline Ades-Mevel, head of EU-Balkans at Reporters Without Borders, told Sky News: "It's a very dark day for Maltese democracy and journalism.

"It is absolutely not expected to see such a murder inside the EU."

Ms Ades-Mevel said the "horrific" killing recalled mafia assassination methods.

"It's extremely violent, and probably also intentionally traumatic," she said.

Image: Thousands gathered for a candlelit vigil in memory of Ms Caruana Galizia

Maltese authorities have vowed to carry out a full investigation and politicians - some of whom were engaged in lawsuits against Ms Caruana Galizia - expressed horror and offered their condolences.

"Everyone knows Caruana Galizia was a harsh critic of mine, both politically and personally, but nobody can justify this barbaric act in any way," Prime Minister Muscat said.

But Matthew Caruana Galizia, also an investigative journalist, said the leader's words were "little comfort".

"If the institutions were already working, there would be no assassination to investigate - and my brothers and I would still have a mother," he wrote.