The 20-year-old Hispanic man killed in a car crash that knocked out power to thousands of customers in Wausau was legally drunk, according to Wausau Police.

Marathon County Medical Examiner John Larson says a toxicology report has determined that Sergio Hernandez's blood-alcohol content was .105.

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In Wisconsin, .08 is considered legally drunk to drive.

Officials say Hernandez was in the country illegally and has a history of using phony identities.

Hernandez had about $200 cash in the car - a 1995 Chevrolet Camaro - which was registered to an Illinois man.

Police Chief Jeff Hardel says they contacted the man and were told he sold the car to Hernandez's brother "a while ago," and that the car has not been registered for more than two years.

The car was also not insured.

Police say Hernandez was the only occupant.

The crash happened at about 3:30 a.m. August 22 on Townline Road and 12th Avenue when the car hit a deer, lost control and hit three utility poles, temporarily knocking out power to more than 4800 residents on the city's east side.

Police say they have not determined exactly how fast Hernandez was driving - just that it exceeded 35 miles per hour.

His girlfriend, Jessica, tells NewsChannel 7 she worked with Hernandez and his father at the Wausau Family Restaurant, and that she does not know why Hernandez was driving.

Co-workers tell NewsChannel 7 they want to help his family pay for the funeral.

They also say Jessica and Hernandez's father have taken a leave of absence from work.