The Nationalist Party has urged the commissioner of police to arraign people involved in the Electrogas power station corruption scandal.

"The Opposition has waited long enough. The Commissioner of Police needs to act. Failure to do so would mean he is condemning himself, like his predecessor, who protected the interests of the few over the interests of justice and the truth," the shadow minister for home affairs, Beppe Fenech Adami said in a statement.

He was reacting to evidence given in court by Matthew Caruana Galizia, the son of murdered journalist Daphne Caruana Galizia, and Europol officials.

Fenech Adami said testimony heard on Tuesday showed how much more remained to be done for justice to be served.

Commissioner Angelo Gafa' had the facts which confirmed what everyone had known - that Daphne Caruana Galizia was killed because of what she knew, and the commissioner had a duty to arraign all those responsible without further delay.