An investigator heading a federal probe into an accident that killed two transit workers in Northern California on Saturday has said that the train was being operated by a trainee, according to the Los Angeles Times. The accident occurred in the midst of a strike by 3,200 workers in the Bay Area Rapid Transit (BART) system.

The Times report follows an article in the San Francisco Chronicle, which cites inside sources involved in the investigation that also reported that the deadly accident occurred during a training run for drivers to replace striking workers. For safety reasons, BART’s contracts explicitly prohibit anyone who is not a certified training operator from running a powered train.

These revelations directly contradict the initial claims from BART management, which said the train was on a maintenance run to keep rust off the tracks and drop cars vandalized with graffiti off at a maintenance yard. They expose the responsibility of management for the workers’ deaths, a result of safety violations that are part of BART’s ruthless campaign against the striking workers.

Even as these revelations emerged, the unions involved—the Service Employees International Union and the Amalgamated Transit Union—were engaged in intense negotiations to end the strike as quickly as possible on the basis of an agreement that accepts all of management’s demands. The unions have refrained from any criticism of management over the deaths, worried that this would increase worker opposition and make the rotten sellout being prepared harder to push through.

According to the Times, “James Southworth, who is in charge of investigating the accident for the National Transportation Safety Board, said the driver/operator was one of two trainees on board with a management trainer when the accident occurred.” BART had initially claimed that it was the manager, a former driver 20 years ago, who was operating the train.

Southworth also reported that the train was traveling 60 to 70 miles per hour at the time, and that the train operators had received radio reports warning of workers on the track. BART communication workers are on strike, and it is unclear who was running dispatch and whether they had experience on the job.

In the prelude to the strike called last Friday, BART managers said they would break the strike with chartered buses and using managers to keep some trains running between downtown Oakland and San Francisco.

Several of the managers, like the one on the train when the two workers were killed, are former train drivers. Others are being trained in a warehouse on Mare Isle with two trains management had set aside for scab training. The unions said at the time that it would be dangerous to run trains with inexperienced replacements.

In reaction to the two workers killed, the unions have refrained from placing any blame on management. Instead the ATU canceled its weekend pickets “out of respect for the families involved,” and issued a bland statement with SEIU expressing their “deepest sympathies.” The union executives are afraid of the anger and disgust that workers feel over the recklessness of management.

The principal aim of the unions is to create the conditions for ending the strike and pushing through a concessions contract. Just an hour before the fatal accident the president of the ATU local, Antonette Bryant, announced that BART’s last contract offer would be put to a vote of the membership.

On Sunday the unions released a new contract that accepted management’s economic demands and gave ground on the question of “work rules.” Under previous contracts BART management is only able to change the way workers are required to carry out their jobs with union consent. This covers things like safety procedures as well as how paperwork is handled.