The workers said several of their colleagues had received similar sized bonus increases but Reuters was unable to establish how many had been awarded a bonus hike. The plant, which makes Model 3 and Model Y, employs around 20,000 workers.

One of the workers said that his performance bonus had doubled this month on the first quarter, when it was cut to 0.785 times the month salary.

The workers said they were not given a reason for why their bonus had increased and if it was related to the previous complaints. But the move comes after Tesla delivered 247,000 units of China-made EVs in the second quarter, the highest level since its Shanghai plant opened.

Tesla did not immediately respond for a request for comment.

In May, Musk paid a late night visit to the plant as part of his first trip to China in three years. He thanked the workers for “the amazing work”, overcoming difficulties and challenges in a speech at the plant.