Belgium overnight Monday raised its alert level to three on a one-to-four scale, which means there is a real chance of an attack while Abdeslam remains at large.
“I advise him to surrender to the police,” his brother Mohamed Abdeslam, who was himself arrested and freed without charge in Belgium, told France’s BFMTV news channel.
“The best thing would be for him to surrender so that the legal system can shed full light on the case. I remind you that Salah has never been able to tell his side of the story to the police and that he is therefore presumed innocent.”
France says that the “dangerous” Salah Abdeslam is wanted in connection with Friday’s attacks and that a third brother, Brahim, was one of the suicide attackers who launched Friday’s carnage in Paris.
Belgian police had detained Mohamed Abdeslam on Saturday as part of a wave of arrests but he was freed without charge on Monday along with four other people. Two further suspects were charged with involvement with terrorism.
“We are a family. We are thinking about him. We are wondering where he is, and if he is frightened, and if he is eating,” the brother said.
Mohamed Abdeslam told Belgium’s RTL television at his family home in Brussels on Monday that his brother “grew up here, studied here, he is a totally normal lad.”
But Belgium decided to raise its general threat level to three overnight Monday because Salah Abdeslam is considered dangerous and possibly heavily armed, Belgian police said.
The level had been raised at the weekend from two to three for big events, but the general level remained at two.
A police raid on Monday aimed at detaining the fugitive in Brussels’ Molenbeek area — a known hub of European Islamist extremism — failed to find him.
“There are indications that he is in Molenbeek. We have not managed to detain him,” Interior Minister Jan Jambon told Flemish public radio.
“I start from the principle that we stay at level three so long as he is at large,” Jambon said.
A friendly football match between Belgium and Spain in Brussels was cancelled following the raising of the country’s terrorist threat level.
During the wave of attacks in Paris, which killed at least 129 people, three suicide bombers blew themselves outside the Paris stadium where France and Germany were playing a friendly.