TUSCON, Az. (WTVO) — Days after going missing in Tuscon, Arizona, country music singer Luke Bell has been found dead. He was 32.

Bell went missing on August 20th, and was found Monday near where he disappeared, according to The New York Post.

Police say Bell’s cause of death remains “unknown.”

Saving Country Music reported that Bell had been diagnosed with bipolar disorder and his “mental state [recently] took a turn for the worse” after a medication change.

Bell was born in Lexington, Kentucky, but was raised in Wyoming before moving to Austin, Texas, to pursue a career in country music.

He collaborated with Margo Price, Alabama Shakes and Langhorne Slim, and opened for Wilie Nelson, Dwight Yoakam and others.