Daphne Caruana Galizia's sons called for the prime minister's resignation today in the wake of her brutal murder on Monday.

"Resign for failing to uphold our fundamental freedoms. Resign for watching over the birth of a society dominated by fear, mistrust, crime and corruption. Resign for working to cripple our mother financially and dehumanise her so brutally and effectively that she no longer felt safe walking down the street," Matthew, Andrew and Paul Caruana Galizia said.

They also refused to endorse a reward for information offered by the government to catch those responsible for planting a car bomb which killed the 53-year-old writer.

In a Facebook post, the three sons said:

"After a day of unrelenting pressure from the President and Prime Minister of Malta for what’s left of our family to endorse a million-euro reward for evidence leading to the conviction of our mother’s assassins, this is what we are compelled to say.

"We are not interested in justice without change. We are not interested in a criminal conviction only for the people in government who stood to gain from our mother’s murder to turn around and say that justice has been served. Justice, beyond criminal liability, will only be served when everything that our mother fought for – political accountability, integrity in public life and an open and free society – replaces the desperate situation we are in.

The government is interested in only one thing: its reputation and the need to hide the gaping hole where our institutions once were

"The government is interested in only one thing: its reputation and the need to hide the gaping hole where our institutions once were. This interest is not ours. Neither was it our mother’s. A government and a police force that failed our mother in life will also fail her in death. The people who for as long as we can remember sought to silence our mother cannot now be the ones to deliver justice.

"A government and a police force that failed our mother in life will also fail her in death. The people who for as long as we can remember sought to silence our mother cannot now be the ones to deliver justice.

The people who for as long as we can remember sought to silence our mother cannot now be the ones to deliver justice

"The police may or may not find out who ordered the assassination of our mother but as long as those who led the country to this point remain in place, none of it will matter – the name of the person who did this will remain a footnote in the history of how our state was dismantled, taken apart piece by piece and devoured by the criminal and the corrupt.

"The Prime Minister asked for our endorsement. This is how he can get it: show political responsibility and resign. Resign for failing to uphold our fundamental freedoms. Resign for watching over the birth of a society dominated by fear, mistrust, crime and corruption. Resign for working to cripple our mother financially and dehumanise her so brutally and effectively that she no longer felt safe walking down the street.

"And before resigning he can make his last act in government the replacement of the Police Commissioner and Attorney General with public servants who won’t be afraid to act on evidence against him and those he protects.

"Then we won’t need a million-euro reward and our mother wouldn’t have died in vain."

READ ALSO: Caruana Galizia son hits out strongly after his mother's murder, describes the scene