Warning: Some viewers may find the images in the video disturbing.

MILWAUKEE (CBS 58) -- Milwaukee Police are investigating a horrific beating that happened on the city's south side.

The attack was all caught on camera. 

The victim's sister says her 36-year-old brother was attacked last Wednesday near 13th and Arthur.

She says he was jumped by two people with a baseball bat.

Gruesome photos showed the injuries to his head.

The man suffered a concussion and loss of vision in one eye.

No arrests have been made.

Milwaukee Police continue to investigate.

A GoFundMe has been set up to help the victim.