The source said it is not yet possible to determine the number of detainees because the steps are still in progress.
According to the same source, the detainees will be transferred to the Braga Court on Tuesday for the first interrogation and enforcement of the coercive measures.
The detained players are aliens who will be in an illegal situation in Portugal.
The Palmeiras Futebol Clube competes in the 1st Division of the Braga County Football Association.
Louisa called the club's headquarters to try to hear someone responsible, but without success.