The cars are allegedly making dangerous right hook turns across bike lanes.

Uber has acknowledged a potentially dangerous problem with its fleet of autonomous Volvo crossovers.

The San Francisco Bicycle Coalition last week issued a warning after observing the cars making "right hook style" turns across bike lanes. Regulations require drivers to first merge into the bike lane before making right hand turns, helping avoid collisions with cyclists.

"This kind of turn ... is known to be one of the primary causes of collisions between cars and people who bike resulting in serious injury or fatality," the coalition wrote in a blog post. "It's also an unsafe practice that we address in all of the safety curriculum we offer to professional drivers, including the videos we consulted on for Uber as recently as this fall."

Speaking to The Guardian, an Uber spokesperson said engineers are working on a fix for the 'problem.'

Uber's autonomous pilot program appeared to experience a smooth start in Pittsburgh. Controversy began to swirl almost immediately after expanding to San Francisco, however, after a dashcam video showed one of the vehicles driving through a red light. California regulators then claimed the company was operating its fleet without required permits. Brushing off threats of legal action, the ride-hailing company claims its service is exempt because it is not yet ready to be operated without a human behind the wheel to take over if necessary.