The EF-3 tornado that spun near El Reno on Friday killed 10 people, including three storm chasers.

Jim Samaras said Sunday that his brother Tim Samaras was killed.

Tim Samaras' son, Paul Samaras, and another chaser, Carl Young, also died.

The men were from Colorado but traveled the Great Plains in search of bad weather.

The three died Friday night near El Reno when an EF3 tornado with winds up to 165 mph hit the Oklahoma City area during rush hour.

The national Storm Prediction Center in Norman said the men were involved in tornado research.