Belgium has issued an international arrest warrant for Mohamed Abrini, another man suspected of helping orchestrate the series of assaults in Paris that left 130 people dead.
The 30-year-old was seen in CCTV footage getting petrol on the Paris-Brussels motorway with another wanted man, Salah Abdeslam, two nights before the November 13 attacks, police said on Tuesday, adding that Abrini is dangerous and probably armed.
In the footage, Abrini can be seen driving a Renault Clio used in the attacks.
Meanwhile, authorities said GPS tracking has shown Abdelhamid Abaaoud, the suspected ringleader behind the Paris attacks who was killed five days later in a shoot-out with police, had returned to the scene of the crime after French SWAT teams arrived.
Paris prosecutor Francois Molins said mobile phone footage places Abaaoud near the Bataclan concert hall while attacks there were still under way.
'More attacks planned'
The chief prosecutor also said on Tuesday that Abaaoud and an accomplice had planned to carry out a suicide attack on the city's La Defense business district the following week.
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Revealing the latest findings of the vast investigation into the attacks, Molins said Abaaoud had aimed to target the area in the west of the capital where many major French companies have their headquarters.
Abaaoud was killed with his female cousin and another man in a shootout with police at an apartment in northern Paris five days after the series of shootings and suicide bombings in the French capital.
"The two terrorists, Abaaoud and the man found next to him, were planning an attack which involved blowing themselves up on Wednesday 18 November or Thursday 19 November, at La Defense," Molins said.
The man killed in the apartment siege who has not yet been identified "is perhaps" the third assailant spotted by witnesses, who sprayed cafe terraces and restaurants with gunfire on November 13, killing dozens, the prosecutor said.