Tunisian IS suspect arrested over attack plot in Germany

German police arrested a Tunisian man on Wednesday suspected of recruiting for the Islamic State group and planning an attack, as they carried out sweeping raids in the west of the country.

A total of 54 offices, homes and mosques were targeted in the dawn raids in and around Frankfurt in the state of Hesse, the prosecutors' office in Frankfurt said.

The 36-year-old Tunisian is suspected of recruiting and leading a 16-member IS cell that was "planning an attack in Germany... but which was foiled at an early stage without a target being chosen", it said in a statement.

The unnamed suspect was in Germany from 2003 to 2013, before returning in August 2015 as an asylum-seeker, the prosecutors said.

Tunisian officials also suspect the man of involvement in a deadly attack on a museum in his homeland in 2015, according to German authorities.

More than 1,000 police were involved in the raids, said Peter Beuth, the interior minister of the Hesse region.

The operation came a day after police in Berlin arrested three suspected extremists accused of planning to travel to foreign "war zones", likely to be either Iraq or Syria, to undergo explosives and weapons training with IS.

The three frequented the same mosque attended by a Tunisian man suspected of ploughing a hijacked lorry into a Berlin Christmas market, killing 12.