The suspect most wanted in connection with the attacks in Paris earlier this month is believed to have fled to Syria, according to a report by CNN.

Sources close to the investigation said French intelligence agencies have concluded Belgian-born Salah Abdeslam is no longer in Europe, having made his way to the Islamic State heartland in the Middle East.

Abdeslam is suspected of driving several of the attackers, among them his brother, Mohammed Abdeslam, to the attack sites in Paris, where they would go on to kill 130 people.

Abdeslam is known to have crossed into Belgium after the November 13 attacks and, along with Mohamed Abrini, seen with Abdeslam two days before the attacks, has been the subject of a massive international manhunt.

Several of the Paris attackers had lived in Brussels, including Abdelhamid Abaaoud, the plot’s orchestrator who was killed in a standoff with French police.

Belgian authorities have arrested five suspects on terrorism charges in a number of raids linked to the Paris attacks, but have admitted they do not know the whereabouts of Abdeslam.

Belgian Justice Minister Koen Geens said Abdeslam was “likely” getting support from others, adding that it was unlikely he could evade security forces without outside help.

Last week, police in northwestern Germany said they were investigating a tip received from a member of the public that Abdeslam may be hiding out in a rural area near Hannover.

But following “an intensive investigation,” police said they found no signs that he had in fact been there.

News agencies contributed to this report.