Tennis superstar Serena Williams fled to the panic room in her LA mansion when she mistook a sports association drug tester for a dangerous intruder. According to TMZ, Serena’s assistant called 911 last Wednesday and told the emergency operator that a prowler had been spotted at her house.

Turns out the intruder was a random drug tester who stopped by unannounced for a urine sample. Cops responded to the 911 call but quickly left the property when the misunderstanding was discovered.

How does she run in those heels?

It was not known whether Williams submitted to the drug test.

Happy 30th Birthday, Serena Williams

VIDEO: Serena Williams Opens 2nd School In Africa