• Tesla fired more than 30 employees at its Buffalo facility in retaliation for a union push, organizers said in a complaint filed with the National Labor Relations Board.
• Tesla Workers United launched a union campaign at the facility, dubbed Gigafactory 2.
• After hours on Thursday, Tesla responded and called the workers' allegations false, saying 4% of Autopilot data labeling team in Buffalo had been terminated due to poor performance.

Dozens of employees at a Tesla factory in upstate New York have been fired just days after launching a union campaign, organizers alleged Thursday.

In a complaint with the National Labor Relations Board, Workers United said Tesla fired more than 30 workers from its Autopilot unit at a Buffalo plant as a retaliatory measure and to discourage union activity. The union urged the NLRB for injunctive relief "to prevent irreparable destruction of employee rights resulting from Tesla's unlawful conduct."

Employees at the Buffalo facility on Tuesday launched organizing efforts under the union Tesla Workers United. Workers said they're seeking a voice in the workplace, along with better pay and job security.

The employees are tasked with labeling videos from the company's cars in order to improve Tesla's driver assistance systems, marketed as Autopilot or Full Self Driving.

The typical data annotation job at Tesla involves identifying and describing objects in short clips captured by cameras and sensors on Tesla's electric vehicles. Data labelers sometimes need to identify overlapping objects, like a wheel in front of a curb or a pedestrian obstructing the full view of a stop sign. They also review crash footage.

Data annotation specialists have their productivity tracked at a granular level. They're rated on how many clips they can accurately annotate over short periods of time.

Last year, Tesla laid off more than 200 employees who did this type of work in an Autopilot office in San Mateo, California. Hiring these kind of workers in Buffalo helped the company avoid paying a penalty to the state of New York, and to meet a commitment to create high tech jobs there.

Workers received an email Wednesday evening laying out a new policy that prohibits them from recording workplace meetings without the permission of all participants, Tesla Workers United said in a release Thursday. The group said that the policy violates federal labor law and flouts New York's one-party consent law to record conversations.

"We're angry. This won't slow us down. This won't stop us," Sara Costantino, a Tesla employee and member of the union's organizing committee, said in a statement. "They want us to be scared, but I think they just started a stampede."

Tesla and CEO Elon Musk have clashed with union proponents for years. In 2017, Tesla fired a union activist named Richard Ortiz, and in 2018, Musk tweeted a comment found to have violated federal labor laws. The NLRB ordered Tesla to reinstate Ortiz and to have Musk delete his tweet, which it said threatened workers' compensation. Tesla has appealed the administrative court's ruling and his tweet remains.

After hours on Thursday, Tesla responded to the Buffalo workers' complaint with a company blog post entitled, "In Response to False Allegations." The recent terminations in the Autopilot team, Tesla said, amounted to about 4% of the employees in that group, and were part of performance review-related cuts being made at the company starting the week of Feb. 12.

Tesla said it identified which employees it would let go on Feb. 3, which the company said was before the union campaign was announced. Tesla also wrote that the Autopilot data labeling team in Buffalo has grown over the last six months from 437 employees to around 675 employees as of the start of this week.

Read Tesla's full response, here.

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