With Brussels still reeling in the aftermath of the deadly bombings this week, the murder of a nuclear power plant security guard and the theft of his badge has compounded fears that Belgium's two sprawling nuclear plants could be vulnerable to attacks.

The security guard was found dead in his home in Charleroi, a post-industrial region known for its derelict factories and slag heaps. Didier Prospero, who worked for US-owned security company G4S, was discovered shot dead in his bathroom on Thursday night. Belgian daily Derniere Heure (DH) reported that Prospero's children found him, and that his dog had also been shot. His security pass was missing but deactivated after his body was found, DH said.

A police spokesperson was unable to provide VICE News with further information about the case due to the ongoing investigation. Belgian prosecutors told DH that they had not found any correlation between the guard's murder and terrorism. Nevertheless, the timing of his death days after the bombings in Brussels fueled concerns that militants could be trying to get their hands on materials to build a radioactive dirty bomb.

A dirty bomb combines radioactive material with explosives, but does not produce the type of devastating blast associated with conventional nuclear weapons. Instead, it seeks to contaminate the area where the device is detonated with radioactivity, creating panic and forcing authorities to launch an expensive and time consuming decontamination process.

Hours after suicide bombings rocked Brussels transport hubs on Tuesday, killing 31 people and injuring hundreds, Belgium's Tihange nuclear plant was partially evacuated, and all workers who were not strictly necessary were sent home early. The head of Belgium's nuclear regulatory agency said on Tuesday that, while there were no direct threats to the plant, the move to partial-evacuation was "based on new information and the events of [Tuesday]. Extra security measures were taken."

However, the claim that there hadn't been a direct threat mounted against Belgium's nuclear infrastructure isn't entirely accurate. In February, Belgian authorities discovered 10-hours worth of secretly recorded video footage showing one of the country's top nuclear scientists coming and going from his home. The material was discovered during a counter-terrorism raid on the home of Mohamed Bakkali, who was arrested and charged with terrorism and murder associated with the November 13 Paris attacks. Ibrahim and Khalid el-Bakraoui — brothers who authorities believe were the alleged suicide bombers at Brussels' airport and subway — are suspected to have planted the camera, which was hidden in bushes near the scientist's house.

Experts and officials have contended that surveilling the nuclear official, who had access to secure areas of a nuclear research facility in Mol, was part of a grander scheme to take him hostage and force him to hand over radioactive material.

DH reported on Thursday that the suicide bombers who self-detonated on Tuesday were originally planning an attack on nuclear facilities. However, as Belgian police started closing in on their extremist network and arrested suspected terrorists such as Salah Abdeslam, DH said, militants were under pressure to carry out an attack as soon as possible, and abandoned the grander plan of targeting Belgium's nuclear infrastructure.

Sébastien Berg, the spokesman for Belgium's federal agency for nuclear control said a potential attack poses a number of risks. First, that terrorists infiltrate the plant and shut down their operations, which would send about half the country into a blackout.

Another fear, Berg said, was of "an accident in which someone explodes a bomb inside the plant." Lastly, Berg said, "the other danger is that they fly something into the plant from outside," which would stop the cooling process of the fuel and force the plant to shut down.

Until two years ago, security around the plants was fairly lax. In 2014, Belgian officials installed security cameras and developed a plan to combat cyberattacks. They also mandated that all employees move in groups to avoid sabotage by a lone wolf.

Just 11 days before the attacks shook Brussels, Belgium's two nuclear facilities — which contain seven reactors — were guarded by unarmed security personnel. On March 11, the Belgian government deployed 140 troops to beef up security at the nuclear facilities, a temporary solution until a new armed police force is trained to take over.

Follow Tess Owen on Twitter: @misstessowen

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