A man wearing a motorcycle helmet was found dead Tuesday on eastbound state Route 94 near Spring Valley overnight, but there was no motorcycle at the scene, according to the California Highway Patrol.
A 911 caller alerted the CHP around 3:35 a.m. that there was a man in the roadway east of Sweetwater Springs Boulevard.
Paramedics started CPR but the man was declared dead at the scene, according to the CHP.
The CHP said officers searching the area found "motorcycle fragments" but were unable to locate the bike that they came from.
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"Preliminary information suggests the male was traveling eastbound on State Route 94 and was involved in a crash," the CHP said in a statement issued Tuesday afternoon, adding that "all investigative leads have not been exhausted."
One theory is that the man may have been a passenger who fell off a motorcycle.
Anybody with any information about the case is being urged to call California Highway Patrol's El Cajon office at 619- 219-6900.