The man, a Tunisian citizen, was arrested at his home in the Meyrin area of Geneva – near to Cointrin airport – on June 14th in a joint operation between the Swiss federal police and Geneva cantonal police.
A spokesman for the public prosecutor, Anthony Brovarone, told the media the Tunisian man was arrested on suspicion of breaking the Swiss law that bans terror groups Al-Qaida and Islamic State and any activity supporting them.
No further details were given.
According to La Tribune de Genève the man is suspected of being a key figure in the recruitment of jihadists on Swiss soil and was sought by Swiss police for at least two years.
The man first arrived in Geneva in 2010. He then lived in Paris for several months during 2012 and 2013 before returning with his wife and children to Geneva's Meyrin district in 2014, said the paper.
It is thought he may have recruited several people in the Geneva area, sending them to fight in Syria and Iraq.
He may also have had contact with a Belgian accused of planning a terrorist attack in Belgium, added the paper.
The man was known to French and Tunisian intelligence services, it said.