BERLIN - A Tunisian man suspected of being a recruiter for the Islamic State group and building a network of supporters to carry out an attack in Germany was arrested Wednesday in Frankfurt as authorities raided dozens of locations. Authorities said that Tunisian officials also suspect the man of involvement in a deadly attack on a museum in his homeland in 2015.
Frankfurt prosecutors said their investigation focused on 16 people aged between 16 and 46. The main suspect, a 36-year-old Tunisian whom authorities didn't identify, was arrested on suspicion of supporting a foreign terrorist organization.
Investigators believe that he had been a recruiter and smuggler for the IS group since August 2015. They suspect that he had built up a network of supporters with the aim, among other things, of carrying out an attack in Germany. However, they say that plans for an attack were at an early stage and no specific target had been chosen.
The main suspect was in Germany from 2003 to 2013, then returned in August 2015 as an asylum-seeker using a different name, authorities said. He was arrested a year later in Frankfurt, because he had not finished serving a 2008 sentence for bodily harm.
Tunisia was also seeking his extradition at the time - the man was under investigation for alleged involvement in planning and carrying out the March 2015 attack on the Bardo museum in Tunis, as well as a March 2016 attack on the border town of Ben Guerdane.
In November, he was released again because he had served out his previous sentence and Tunisia had failed to provide full documentation to support his extradition within the required 40-day deadline, prosecutors said. However, he was kept under round-the-clock surveillance until Wednesday's arrest.
The spokesman for Tunisia's national prosecutor, Sofiane Selliti, said Wednesday that authorities were awaiting formal identification from Germany to confirm that the suspect is the man sought and to begin formal extradition proceedings.
Wednesday's raids covered 54 apartments, business premises and mosques in Frankfurt and the surrounding region. Officials said the raids followed a four-month investigation.
In a separate case, prosecutors in Berlin said that they arrested three people Tuesday night suspected of planning to travel to Syria or Iraq to undergo explosives and weapons training with IS.
All three were associated with the Fussilet mosque in Berlin, known as a gathering point for radicals, said Martin Steltner, a spokesman for prosecutors.
Berlin Christmas market attacker Anis Amri - a Tunisian who used multiple identities and whose asylum request had been rejected - visited the mosque shortly before his Dec. 19 rampage, in which 12 people were killed.
On Wednesday, Germany's Cabinet approved a plan that will allow authorities to make extremists deemed to pose a possible security threat wear electronic ankle monitors - part of a package of measures meant to avoid a repeat of mistakes made in keeping track of Amri.