France wants Paris attacks suspect Salah Abdeslam extradited from Belgium “as quickly as possible”, President Francois Hollande says.
Abdeslam was wounded and arrested in a dramatic raid in Brussels on Friday after four months on the run.
“Our fight is not over,” Mr Hollande said. Senior security officials both in France and Belgium are meeting on Saturday to assess the situation.
The Paris attacks, claimed by so-called Islamic State (IS), killed 130 people.
Abdeslam, a 26-year-old French national born in Brussels, had lived in the Molenbeek district of the Belgian capital before the Paris attacks.
He is believed to have returned to Belgium immediately after the attacks, in which his brother Brahim blew himself up.
The subject of a massive manhunt, Abdeslam was arrested about 500m from his home.
Another man arrested, Monir Ahmed Alaaj, was also on a wanted list, Belgian prosecutors said.
Three members of a family accused of harbouring Abdeslam have also been detained.
The raid came after Abdeslam’s fingerprints were found in a flat in another Brussels district, which was raided on Tuesday.
Abdeslam was wounded in the leg as police moved in. Dramatic footage showed him being bundled into a police car after a volley of gunfire. He was discharged from hospital on Saturday.
The French president said Abdeslam’s arrest was “an important moment”.
“The battle against terrorism does not end tonight, even though this is a victory,” Mr Hollande told a news conference with Belgian Prime Minister Charles Michel.
“We must catch all those who allowed, organised or facilitated these attacks and we realise that they are a lot more numerous than we thought earlier and had identified,” he said.
Mr Michel said the raid had come after “intense” detective work and said it was a “very important result in the battle for democracy”.
Prosecutors said the second wanted man arrested in Molenbeek, Monir Ahmed Alaaj, had travelled with Abdeslam to Germany last October, where his fingerprints were taken during an identity check.
A false Syrian passport in Alaaj’s name and Belgian identity papers under an alias were found in a flat in the southern suburb of Forest that was raided on Tuesday.
Abdeslam’s fingerprints were also found in the Forest flat.
One man – identified as Algerian national Mohamed Belkaid and linked to the Paris attacks – was shot dead in Tuesday’s raid.
Officials have identified most of the people they believe to have carried out the assaults.
Most of the suspects either died during the attacks or were killed in subsequent police raids.
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