Police say a 62-year-old man died Saturday morning after he crashed his motorcycle on the highway.
Authorities say the accident happened just after 11 am Saturday on IH 35.
According to police, the man was riding southbound on IH 35 when he tried to merge on to Loop 410.
The man lost control of the motorcycle and slammed into a concrete barrier.
Police said he was wearing a helmet, but suffered a major injury when his head struck a metal sign.
An off-duty nurse from SAAMC, who was also riding on a motorcycle, stopped to help him.
"First responders from the military base that were off duty made it to the scene, and they started performing CPR before we got there," said officer Robert Deckard.
The man was transported to SAAMC in critical condition and died a few hours later, said police.
Deckard said the man was not speeding when he lost control of the motorcycle.
Investigators believe alcohol did not play a role in the accident.
Police have not released the man's name.