Malta’s prime minister has announced he will stand down in January following controversy surrounding the murder of a prominent journalist on the island.

Opposition politicians have repeatedly called for Joseph Muscat to quit as the investigation into her murder prompted claims of corruption that led all the way to the government.

Daphne Caruana Galizia, 53, who was killed by a car bomb in 2017, had investigated and unearthed corruption at all levels on the Mediterranean island.

Close to 20,000 Maltese citizens jammed the street outside the courthouse in the capital, Valletta, in what was by far the largest turnout so far in weeks.

Protesters demanded justice – and Mr Muscat’s resignation.

Earlier this week, two government ministers resigned over alleged financial ties to a wealthy businessman charged with involvement in the murder. Mr Muscat had prompted anger by resisting calls for them to be dismissed.

He stepped down just 24 hours after the businessman, Yorgen Fenech, was charged with being complicit in Ms Caruana Galizia’s murder.

In a televised message on Sunday night, Mr Muscat said he had informed the nation’s president that he would quit as leader of the governing Labour party on 12 January and that in the days after he would resign as prime minister.

His former chief of staff, Keith Schembri, one of those who resigned and had been arrested for questioning in the investigation, was among government members targeted by the journalist’s investigative reporting.

He was released after questioning and denies wrongdoing.

Participants in the street protest carried photos of Ms Caruana Galizia, as well as placards with the last words she wrote on her blog.

“The situation is desperate,” she had written, referring to what she unearthed with her digging into suspected widespread corruption in political and business circles.

On the placards, protesters added the word “still” before “desperate”.

Affixed to the gate outside the courthouse were copies of a photo that was published on Saturday by Malta Today showing Ms Schembri with the alleged middleman in the case, taxi driver Melvin Theuma. It was unclear where and when the photo was taken.

Mr Theuma recently was granted immunity from the prosecution in exchange for giving details on who was behind the bombing.

Shortly after the blast, three men were arrested for allegedly carrying out the actual bombing. No trial date has been set for those three.

Among the demonstrators were Ms Caruana Galizia’s family, including her parents, who walked at the head of the protest behind a banner with the word “justice”.