According to police, officers responded to the business on Lake Pine Drive on Wednesday afternoon.
Apex police said a "violent individual" made public threats toward President Trump, leading to the evacuation of the building. The messages were found written on the back windshield of the car.
The bomb squad's robot was launched to check out the car.
Police tell ABC11, as part of that response, the individual's vehicle was searched for explosive devices as a precaution.
Former FBI bomb technician Frank Brostrom says in situations like that, using technology is the safer option.
"That's why 99% of the time you're going to use a robot. The robots are equipped with cameras and microphones, they have a disruptor cannon on it. And they're very agile. These bomb technicians are trained on how to use those claws, just like you would your hand to be able to open doors and grabs things and pull things out," he says.
The response raised a lot of concern in Apex as people wondered what was going on, but the Mayor said he's proud of how his officers responded.
"They're going to take care of the town in a way that they do every single day. So, I'm grateful and thankful for all they do every day. But in this situation, I'm even more grateful for their response," says Mayor Jacques Gilbert.
But as for what led up to this, Brostrom says a Secret Service response is rare, but not unheard of in the current political climate, and there are still a lot of unanswered questions.
"What did the person say? Was it a 911 call or they just found the car that way? And why was the Secret Service? Those are all be interesting, facts when they come up," he says.
The person involved has been detained. Police said charges are pending.
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