12:04 PM PT -- A witness to the incident tells TMZ ... customers at another table were being rude and vulgar to Jamie, and he asked them to stop since his family was present ... which is when someone at that table allegedly threw the glass that hit him in the face.

10:59 AM PT -- A spokesperson for Jamie tells TMZ ... “Jamie Foxx was at his birthday dinner when someone from another table threw a glass that hit him in the mouth. He had to get stitches and is recovering. The police were called and the matter is now in law enforcement’s hands.”

Jamie Foxx was allegedly involved in a fight in the dining room of Mr. Chow Friday night ... and he may have been injured, TMZ has learned.

Law enforcement sources tell us ... police were called to the popular, high-end Beverly Hills restaurant around 10 PM on the report of a fight inside.

For the moment, details are murky ... but we are told by police sources that Jamie was involved in the alleged altercation -- however, he was gone by the time police arrived.

An assault report was taken and Jamie's name is listed as a party involved in whatever went down ... so police will be reaching out to him.

A witness of the alleged fight said that Jamie may have been hurt ... but if that's true, he did not stick around for medical attention.

We know Jamie was at the hotspot with his family ... 'cause he was snapped going in with his daughters Corinne and Anelise Foxx, and his former partner, Kristin Grannis.

Don't forget, we chatted with Jamie at Mr. Chow's earlier this week for another celebration ... following the release of his Netflix Special.

We have reached out to Jamie's team for more info ... so far, no word back.