Practice was interrupted for some drivers on Thursday at Daytona International Speedway after a bomb threat phone call was made.
The anonymous bomb threat halted practice, but the Daytona Beach Police Department swept through the racetrack and didn't find any traces of explosive devices.
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The police department released a statement after not finding any explosives.
"On Thursday afternoon, June 29, 2017, a call was received at the front desk of the Daytona Beach Police Department regarding a bomb threat at the Speedway. The caller said he had placed multiple bombs on Speedway property. A thorough check of the property was done and nothing was found an hour into the search."
The bomb threat was made at 2:57 ET, and the caller told police he placed multiple bombs throughout the facility.
Police were able to obtain the phone number of the caller, and they are currently trying to identify the suspect.
The remainder of the practices and races are still on schedule for this weekend for the Coke Zero 400 at Daytona International Speedway.
(h/t Autoweek)