Sen. Elizabeth Warren (D-Mass.) is calling for an investigation into Tesla and its potential conflicts of interest following CEO Elon Musk’s acquisition of Twitter last fall.

In a letter to U.S. Securities and Exchange Commission (SEC) Chair Gary Gensler Monday, Warren said she is requesting an investigation into Tesla and the company’s disclosures on how its board is “managing the apparent conflicts of its Chief Executive Officer, Elon Musk.”

Warren said Musk’s actions since he purchased Twitter and became its CEO — while still remaining Tesla’s CEO — “have raised concerns about conflicts of interest, misappropriation of corporate assets, and other negative impacts to Tesla shareholders.”  

“Tesla’s board has a legal obligation to serve its shareholders. I’m urging @SECGov to investigate,” Warren added in a tweet.

Warren’s office did not immediately respond to a request for further information.

The Hill has reached out to Tesla for comment on the letter, which was first reported by CNBC.

Monday’s letter echoes concerns Warren addressed last year in a letter to the chairman of Tesla’s board where she said she was concerned the company’s board “failed to meet” its “legal duty.”

Warren said Monday the board has so far “refused to provide answers.”

“Despite recent and repeated calls from investors to address these actions, the Board appears to have failed to uphold its legal duty to ensure that Mr. Musk act in the best interest of Tesla,” she wrote.

“Mr Musk’s personal wealth — and his personal relationships with Board members — do not shield him or the Tesla Board from meeting basic SEC governance and disclosure rules,” Warren added later.

Musk came under fire last year when he began selling billions of dollars worth of Tesla stock as he worked to purchase Twitter for $44 billion, according to filings with the SEC.

He has continued to draw ire from some lawmakers, particularly on the left, over his handling of the platform.

Since purchasing the social media platform, Musk has made a series of controversial choices including ousting some top executives, implementing mass layoffs and starting the Twitter Blue program, requiring users to pay a monthly subscription fee for the verification checkmark.

On Saturday, Musk announced Twitter is experiencing a nearly 50 percent drop in advertising revenue while also dealing with heavy debt flow, despite telling the BBC in April the platform is “roughly breaking even.”