Fatima Hadfi, who said she was the mother of Bilal Hadfi who blew himself up outside the Stade de France in Paris, phoned into Maghreb TV late yesterday, surprising the presenter.
In the recording of the call on the station's website, she complained that the French authorities were still holding her son's body and she could not understand why it had not been released for burial.
The presenter asked her to explain how Bilal Hadfi, 20, had become involved with the jihadist attackers, several of whom came from Brussels, and why she had not seen any warning signs before he left for Syria in February. "You could not see anything (different) with him.
He was like everybody else," Fatima Hadfi said, speaking mostly in French. "He was a good boy, friendly and helpful but despite all that, they knew how to get around him." Asked what role her son had played in the attacks, she said: "I have no idea at all."
Press reports yesterday said the Belgian authorities were questioning staff at Bilal Hadfi's college in Brussels after warnings that he was becoming radicalised were missed.
The college reportedly informed the education authorities of their concerns in April after he went to Syria but the warning was not passed on to police and only came to light after the November 13 attacks.
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Fatima Hadfi told Maghreb TV that she was sure that people listening to her would wonder how she could not have noticed any changes in her son's behaviour.
"I have said that to myself. I should have listened more closely, I should have been closer to my children," she said. Maghreb TV Belgique serves mainly the local Moroccan community in Belgium.
The Belgian authorities are still looking for suspects linked to the attacks on a Paris concert hall, restaurants, bars and the national stadium which left 130 people dead.
On Thursday, they announced they had charged a ninth person. AFP could not independently verify the identity of the woman who called into the station as Fatima Hadfi.