German prosecutors confirm they have detained a 40-year-old Tunisian man they think may have been involved in last week's truck attack on a Christmas market in Berlin. 

The Associated Press reports that the man was detained during a search of his home and business. 

Prosecutors said the man's phone number was saved in the cellphone of Anis Amri, a fellow Tunisian believed to have been the driver of the truck that rammed through a crowd on December 19, killing 12 and injuring dozens. 

Anis Amri was killed in a shootout with police Friday. 

Prosecutors have until Thursday night to determine if the case against the new suspect holds up to the extent that they can seek a formal arrest warrant. That would allow them to keep him in custody pending possible charges.