A former MMA fighter is going after the head of the UFC

Dan Quinn has left Dana White multiple voicemails, which were obtained by TMZ, in which he threatens the UFC president.

Quinn's career lasted from 2001-2010, but he never fought in the UFC. Still, he's publicly spoken out against White for years, and now has taken it to the extreme.

Quinn recently got hold of White's private work number and has left him several messages in which he threatens to kill him.

Prior to getting White's phone number, he put a video on YouTube in he said he would beat White to death.

In the phone message, Quinn claims White sent someone to threaten the life of Quinn and his kids.

I just want you to know, since you're bringing that to me, you should be worried about your own safety, Quinn told White in a voicemail. I'm gunna shoot right in the f****** head,

The voicemails have been turned over to the Las Vegas police department, which is investigating the matter.

Click here to listen to Quinn's voicemails, and see the videos in which he also threatened White.