BRUSSELS - Dozens of Belgian police, including armed special commandos, surrounded houses in a residential street in the district of Molenbeek on Monday.Despite conflicting reports, the public broadcaster denied rumors that a man wanted in connection with the Paris attacks was arrested.State-controlled RTBF carried a denial of a report by private broadcaster RTL that Saleh Abdeslam, a 26-year-old Frenchman based in the Belgian capital, had been detained.Police said the operation was related to the Paris attacks.Reuters journalists at the scene in Molenbeek said there had been little movement around police lines. Armored vehicles remained in position.The poor district of Molenbeek, home to many Muslim immigrants, has been at the center of investigations of militant attacks in Paris over the weekend, after it emerged that two of the attackers had lived in the area.Reports said Abdeslam was pulled over on the French-Belgian border on Saturday hours after the attack. He was one of three passengers in the vehicle. Yet he was shortly released, upon presentation of an ID, following brief questioning.One of the brothers died in the attacks, while the second is under arrest in Belgium, a judicial source said.INVESTIGATION SUSPECTS BELGIAN NATIONAL AS MASTERMIND BEHIND PARIS ATTACKSA Belgian national currently in Syria and believed to be one of Islamic State's most active operators is suspected of being behind Friday's attacks in Paris, according to a source close to the French investigation."He appears to be the brains behind several planned attacks in Europe," the source told Reuters of Abdelhamid Abaaoud, adding he was investigators' best lead as the person likely behind the killing of at least 129 people in Paris on Friday.According to RTL Radio, Abaaoud is a 27 year-old from the Molenbeek suburb of Brussels, home to other members of the militant Islamist cell that carried out the attacks.In February of this year, Islamic State's online magazine Dabiq carried an interview with an Islamist bearing that name and boasting of having traveled through Europe unnoticed by security forces to organize attacks and procure weapons.Abaaoud was also named in various media last year as the elder brother of a 13-year-old boy who left Belgium to become a child-fighter in Syria.