More than six Cruise robotaxis stopped operating and sat on a street in San Francisco, according to a Tech Crunch report. The robotaxis blocked traffic for a few hours until employees arrived to manually move the autonomous vehicles.

“We had an issue earlier this week that caused some of our vehicles to cluster together,” a Cruise spokesperson told Tech Crunch. “While it was resolved and no passengers were impacted, we apologize to anyone who was inconvenienced.”

This incident happened less than a week after Cruise started its first fully driverless commercial robotaxi service in San Francisco, according to the report. Initially, the autonomous vehicles are operating between 10 p.m. and 6 a.m. on designated streets.

The San Francisco Municipal Transportation Authority (SFMTA) did not respond to Tech Crunch’s request for information about how it handles these types of situations with autonomous vehicles and whether Cruise would receive a fine for blocking the intersection.