BERLIN (AP) — German investigators say they have searched the apartment of a witness in their probe of an alleged hacking case that saw hundreds of politicians' and celebrities' private information posted online.

The Federal Criminal Police Office said the search took place in Heilbronn in southwestern Germany on Sunday. It didn't give further details in a Twitter post Monday. The office did say that isolated cases of compromised data were reported to police last year.

German media reported last week that as many as 1,000 politicians and celebrities are believed to have been affected by the breach of data.

Authorities are still investigating who was behind the theft and publication of the information, which included data on members of all parties in parliament except those from the far-right Alternative for Germany party.