BERLIN — Two brothers suspected of planning an attack on a shopping mall in Oberhausen, in the western German state of North Rhine-Westphalia, have been arrested, the police said early Friday.

The brothers, 28 and 31, were born in Kosovo. They were arrested in Duisburg. The authorities acted on information provided by security sources, the police said in a statement.

It was not clear if there was any connection with Monday’s attack on a Christmas market in Berlin, which killed 12 people.

The names of the brothers were not released, and the police provided no further details on what had led to the arrests.