The Dutch prosecutors have requested the extradition of the suspects.
German investigators searching the Berlin home of Daniela Klette, a suspected leftwing terrorist arrested in February, have secured thousands of evidence.
German police investigations believed that the 30-year-old man who sat at a table outside the café was the intended target of the attack.
A spokesman for the public prosecutor’s office in the city of Celle near Hanover told dpa that the searches were ongoing.
The German police, while searching for a stolen bicycle by chance, discovered the dead body of a 63-year-old woman.
They were suspected of plotting a terrorist attack in accordance with the aims and ideology of the extremist militia organisation Islamic State.
The terrorist was said to have remained on the run for decades and turned up equipment for forging official documents.
The suspects were said to have been involved in smuggling people across the English Channel.
Until this new role, Mr Chukkol was the director of operations of the commission.
They were accused of forming or supporting a criminal organisation and organising fundraising to finance the group’s alleged crimes.
