While Google was test driving its self-driving cars near the company's headquarters in Mountain View, California on Thursday, one of the cars was pulled over by police for going much slower than the posted speed limit.

The test car pulled over by the Mountain View Police Department was one of Google's cars that has a top speed of just 25 miles per hour, Tech Radar reports.

The posted speed limit in the area was 35 miles per hour. The police officer noticed that traffic was being backed up by the slow moving vehicle, traveling just 24 miles per hour, and decided to pull it over, CNet reports.

"As the officer approached the slow moving car he realized it was a Google autonomous vehicle," the Mountain View Police Department wrote in a blog post. "The officer stopped the car and made contact with the operators to learn more about how the car was choosing speeds along certain roadways and to educate the operators about impeding traffic per 22400(a) of the California Vehicle Code."

Facebook user Zandr Milewski snapped a picture of the traffic stop and said that he talked to the car's co-pilot, a Google employee required to ride along with the self-driving car in case of emergencies.

The co-pilot told Milewski that "apparently MVPD (Mountain View Police Department) doesn't get NEVs (Neighborhood Electric Vehicles) and pulled them over to ask why they were all going so slow."

Google is happy with its self-driving vehicles so far. The company says that it has an excellent driving record.

"Like this officer, people sometimes flag us down when they want to know more about our project," the company said in a blog post. "After 1.2 million miles of autonomous driving [that's the human equivalent of 90 years of driving experience], we're proud to say we've never been ticketed!"