This is a breaking/developing story. He is being detained. There is an accusation. Facts and details are being gathered. He is presumed innocent until proven guilty.

Here's what we know from Huffpost.

U.S. singer Chris Brown and two other people are in custody in Paris after a woman filed a rape complaint, French officials said Tuesday.

Brown was detained Monday on potential charges of aggravated rape and drug infractions and remained in custody Tuesday, a judicial official said. Investigators have another two days to decide whether to let him go or file preliminary charges.
One of Brown's bodyguards is one of the two people in custody.
Read the complete story here.
Brown's publicist at Sony Music had no comment on the situation nor any word on what he was doing at Paris at the time.