(CNN) -- An aircraft crashed Saturday afternoon during a demonstration at a West Virginia air show, killing the pilot, the West Virginia Air National Guard said.

No one on the ground was injured.

It was not immediately clear what caused the accident at the 2011 Thunder Over the Blue Ridge Open House & Air Show in Martinsburg, West Virginia. The pilot was flying a T-28 aircraft.

CNN iReporter Jennifer Clark took pictures of the 2:30 p.m. ET crash, showing flames and black plumes of smoke rising from the ground.

"We saw a flash of light ... and heard the explosion sound," she told CNN's Don Lemon. "It was scary."

"You just heard the whole crowd gasp simultaneously and everybody just kind of went silent and was just watching what was going on," she said.

The West Virginia crash came one day after another deadly air crash.

A pilot lost control of his vintage plane during an air race in Reno, Nevada, on Friday, plummeting toward thousands of spectators before narrowly missing a grandstand and slamming into box seats. Nine people, including the pilot, died in that accident, according to local police.