TULSA, Oklahoma - Tulsa Police say a 26-year-old motorcyclist is dead after he crashed near Admiral and Memorial early Thursday.

Officers have not yet released the man's name, pending notification of next of kin, but say the man was not wearing a helmet.

Police say the crash happened just after 12:30 a.m. when his 2016 Harley Davidson motorcycle crash in the 8100 block of East Admiral.  

Officers said the eastbound motorcycle hit a curb causing the rider to lose control and hit a street sign. The impact threw the man from the bike.

First responders and even some witnesses to the crash tried to save the man, but police said he died a short time later. 

An investigation into the crash continues.