Via the New York Times:
Belgians sought to make sense on Wednesday of a spasm of killing by a man with a history of trouble with weapons and drugs who unleashed his attack near a Christmas market at a historic square, bringing random death to a familiar scene of European holiday bustle.
(...)
“He didn’t feel at all Moroccan,” one lawyer said, adding that he “didn’t speak a word of Arabic and wasn’t a Muslim,” and that “he felt Belgian.” At other points, the interview quoted the lawyers as saying that he “was crazy about weapons, but as a collector”; “he felt that he’d not had much luck in life”; he “thought he’d been unfairly treated by the justice system.”
One said his action was that of “a tormented soul who was at the end of his tether, cut off from the justice system and from society.”
(source)
See also here for more on Amrani's history.