Yevgeny Ivanov said he had been attacked by two men at around 2:30 p.m. Moscow time (11:30 GMT) Sunday when exiting the entrance of his apartment building in the town of Kolpino near St. Petersburg.
"I went to a store. When exiting the elevator, I received several professional blows into the face. There were two of them. As a result of an unexpected attack, I fell down and while I was getting to my feet, I heard the words "greetings from the trade union," Ivanov told RIA Novosti.
Ivanov earlier reported about anonymous threats, which he linked to his trade union activity. Police then opened a probe following his application but later refused to institute criminal proceedings saying they had found no evidence of a crime.
Ivanov became the head of the GM's Petersburg car factory trade union about two months ago. The recently established trade union announced it would seek changes in the system of labor payment at the car factory.
This is not the first incident linked to attempts to exert pressure on trade union leaders. In 2008, unidentified assailants attacked the trade union head of the Ford car plant near St. Petersburg. The criminal investigation opened into the case has not yielded any results so far.
General Motors opened an automobile factory in St. Petersburg early in November. The plant's first assembly line is designed to roll out 60,000 Chevrolet Captiva and Opel Antara sport utility vehicles annually.