This May 13, 2014, file photo shows a Google self-driving Lexus at a Google event outside the Computer History Museum in Mountain View, Calif. Google will release monthly reports on the performance of its self-driving cars, and it disclosed summaries of the accidents that involved the vehicles. The company said Friday, June 5, 2015, as it has in the past, that its cars were not to blame for any of the accidents. (AP Photo/Eric Risberg, File)

Google is disclosing more details about the 12 accidents involving its self-driving cars so far as part of a commitment to provide monthly updates about the safety and performance of the vehicles.

The summary released Friday described all of the collisions as minor, saying no injuries were reported. As it has been doing for several weeks, Google said that the self-driving technology was not to blame for any of the accidents. In one case, however, an employee used the self-driving car to run an errand and rear-ended another car that was stopped in traffic. Google had previously disclosed that accident, which happened in August 2011.

Google's breakdown of the accidents came just two days after company co-founder Sergey Brin told shareholders that the company had already disclosed most of the pertinent information about the crashes.

Consumer Watchdog, a group that has been a longtime Google critic, has been pushing the Mountain View, California, company to release all of the accident reports filed with the California Department of Motor Vehicles and other law enforcement agencies. Dissatisfied with Google's accounting, Consumer Watchdog on Friday renewed its call for the company to release the official accident reports.

The Associated Press has asked Google and the California Department of Motor Vehicles for the reports. Both have refused, citing privacy concerns.

While the latest disclosures fell short of providing the official accident reports, they did give previously unreleased information on the locations and dates and circumstances of the 12 accidents.

Google Inc. started testing the cars in 2009, and the first accident was in May 2010.

The company says six of the accidents happened while the car was in autonomous driving mode. The other six happened while staffers were driving, including one incident where the car was hit by another driver who rolled through a stop sign. Google says the self-driving car automatically applied the brakes when it detected the other vehicle, and Google's driver took manual control once the brakes were applied. The Google vehicle sustained some damage.

All but two of the accidents happened in Google's hometown of Mountain View, where the company plans to begin testing its latest self-driving car—a pod-like vehicle—this summer.

While several of the accidents happened at low speeds or while the car was stopped, in one case a Google vehicle was driving 63 miles per hour on a highway in San Jose, California, when another vehicle veered into its side.

Google's cars have been involved in four accidents so far this year, according to the company. It says the cars travel about 10,000 miles a week on public streets. The vehicles have driven about one million miles in autonomous mode and Google's drivers have been in control for 800,000 additional miles.

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