Salah Abdeslam, a militant suspected to be involved in the Nov. 13 Paris terrorist attacks, may have sneaked across Europe and reached Syria, a French intelligence source close to the investigation told CNN Monday. Several raids have been conducted over the past few days in the Belgian capital Brussels for Abdeslam.

Police are also investigating reports that Abdeslam purchased detonators at a fire shop on the outskirts of Paris, before the well-coordinated shootings and suicide bombings in the French capital, CNN reported. The store manager of the Saint-Ouen l'Aumone shop, Les Magiciens du Feu or "Fire Magicians," alerted police after Abdeslam's photograph was made public, French newspaper Le Parisien reported. 

Authorities believe that Abdeslam was meant to be the eighth suicide bomber in the Paris attacks but fled the city after taking part in the shootings on several restaurants and cafes along with other militants. It was unclear what made him change his mind. A suicide vest found left in a bin close to one of the attack scenes in Paris was believed to belong to Abdeslam.

Investigators began working on the assumption that Abdeslam fled Brussels after another suspect, Ali Oulkadi, revealed that he had picked up the 26-year-old fugitive and a friend at a subway stop in suburban Brussels the day after the attacks, which were claimed by the Islamic State group, also known as ISIS.

"He did not know it was Salah and did not recognize him immediately when he arrived because he was wearing a cap," Oulkadi’s lawyer Olivier Martins reportedly said. "In the car, Salah told him that his brother, Brahim, had killed people in Paris and had blown himself up. For my client, a childhood friend of the two brothers, it was a shock. He could not understand it and could not think clearly."

Last week, a Belgian court ordered that Oulkadi be detained for a further 30 days for questioning. He is reportedly one of the six people detained by Belgian authorities in connection with the attacks. Oulkadi’s lawyer has insisted that his client did nothing wrong "and is absolutely not radicalized."

An international arrest warrant issued for Abdeslam just days after the attacks described him as 5 feet 7 inches tall and "dangerous."

Earlier, German newspaper Bild also reported that Abdeslam may have fled Brussels and was planning on entering Germany. However, the news was not confirmed by authorities.

Abdeslam’s brother, Mohamed Abdeslam, who was taken into custody for questioning last month, issued a call for his brother to surrender. He denied being connected to the Paris attacks and also said that he was unaware that his other brother Brahim blew himself up in a café in one of the coordinated assaults.

“We would rather see Salah in prison than in a cemetery,” Mohamed Abdeslam told Belgian broadcaster RTBF on Nov. 20. “We would like Salah to hand himself in ... so that he can give us the answers that we are waiting for.”