SAN FRANCISCO, Dec 5 (Reuters) - The Communications Workers of America union filed a federal labor charge against Alphabet Inc’s Google on Thursday, accusing the company of unlawfully firing four employees to deter workers from engaging in union activities.

The complaint, seen by Reuters, will trigger a National Labor Relations Board (NLRB) investigation into whether Google violated the four individuals’ right to raise concerns about working conditions. When violations are found in such cases, the NLRB typically tries to help accusers and companies reach a settlement.

Google did not immediately respond to a request for comment. (Reporting by Paresh Dave; Editing by Muralikumar Anantharaman)