TMZ reports Chris Brown is in jail for violating a judge’s order to remain in rehab after he was kicked out of the Malibu rehab facility where he’s been living for the last four months.

Sources familiar with the situation tell TMZ … Brown was thrown out of the rehab facility this morning, for violating “internal rules.” We do not know precisely what Chris did, but we’re told it did not involve violence or drugs.

Sources tell TMZ … Chris was caught having “an inappropriate relationship” with a female worker at the beginning of the month, but that is NOT why he was thrown out today.

As you recall, Chris was previously thrown out of a different facility for throwing a rock at his mom’s car window.

Chris was picked up by L.A. County Sheriff’s deputies this afternoon and is now in jail …being held with no bail.