In a post on Facebook on Tuesday, Matthew Caruana Galizia described how he ran toward his mother's car after hearing the explosion outside their home, only to see "my mother's body parts all around me."He said that she had been "targeted" and added that a "culture of impunity has been allowed to flourish by the government in Malta." "My mother was assassinated because she stood between the rule of law and those who sought to violate it, like many strong journalists," he wrote."But she was also targeted because she was the only person doing so. This is what happens when the institutions of the state are incapacitated: the last person left standing is often a journalist. Which makes her the first person left dead."Caruana Galizia, who had led the investigation into the Panama Papers and alleged corruption within political circles in Malta, was killed Monday after her car exploded soon after she left her home in Bidnija, close to the town of Mosta.A police investigation is underway with officials from the FBI and Dutch forensic experts also examining evidence, according to the Maltese government.A vigil was held on Monday night with mourners lighting candles in Sliema, near the capital city of Valletta.Caruana Galizia's popular blog, "Running Commentary," was one of the most influential within Maltese politics. It was a leading factor prompting Prime Minister Joseph Muscat to call early elections four months ago after she alleged that he and his wife were linked to the Panama Papers scandal.The couple denied allegations that they had used secret offshore bank accounts to hide payments from the ruling family of Azerbaijan.In an interview with CNN on Tuesday, Muscat said that there was "no doubt" that this was a targeted attack and called it a "very professional job."He rejected the idea that the Maltese government "has anything to do with this," and added that he needs "to make sure that everyone has, in our country, as we have, the right to say and write whatever we want."Muscat also said that there "will be absolutely no impunity for anyone" involved in the attack.Caruana Galizia was highlighted by politics website Politico as one of 28 individuals who would have a major impact on Europe in 2017 after her work in exposing corruption within Malta's political scene. Politico described her as "a one-woman WikiLeaks, crusading against untransparency and corruption in Malta."Her son, Matthew, also a journalist, said that his mother's death was "no ordinary murder."He wrote how he would never forget "running around the inferno in the field, trying to figure out a way to open the door, the horn of the car still blaring, screaming at two policemen who turned up with a single fire extinguisher to use it."In her blog, the 53-year-old journalist regularly reported on allegations of corruption across the country's political sphere.In her final blog post, which was published around 30 minutes before the explosion, she wrote: "There are crooks everywhere you look now. The situation is desperate."In a statement issued in the aftermath of the explosion, Muscat called the incident "barbaric" and said it "goes against civilization and dignity.""Everyone is aware that Ms. Caruana Galizia was one of my harshest critics, politically and personally, as she was for others, too," Muscat said in the statement. "However, I can never use, in any way this fact to justify, in any possible way, this barbaric act that goes against civilization and all dignity."But Muscat's statement has not reassured Caruana Galizia's son. He said that Malta had become a "mafia state… where you will be blown to pieces for exercising your basic freedoms, only for the people who are supposed to have protected you to instead be celebrating it."He added: "If the institutions were already working, there would be no assassination to investigate – and my brothers and I would still have a mother."
CNN's Christiane Amanpour contributed to this report.