A pension fund representing Detroit police and firefighters has sued Tesla Inc.'s board directors, including CEO Elon Musk, alleging that they siphoned off company funds by drawing outsized compensation packages over a period of three years, Bloomberg News reported June 18, citing court documents.

The lawsuit, brought by the pension fund invested in Tesla, accuses company directors of using their positions "to enrich themselves at the company's expense" by awarding themselves millions in "excessive compensation," according to the report.

The complaint, filed June 17 in the Delaware Chancery Court, reportedly names directors including Oracle Corp. founder Larry Ellison, former 21st Century Fox Inc. CEO James Murdoch and Musk's brother Kimbal Musk.

According to Bloomberg, the pension fund is asking the court to find that the board's pay packages were excessive and to make the board members pay the company back.

Tesla did not immediately respond to Bloomberg's request for comment.

Bloomberg News reported June 17 that proxy advisory firm Glass Lewis has joined Institutional Shareholder Services in recommending that Tesla shareholders vote against the reelection of the company's Chairwoman Robyn Denholm over corporate governance concerns.

In May, Tesla awarded Musk with the first performance-based payout, worth about $770 million, under its 2018 CEO Performance Award program.