Investing.com -- Sen. Elizabeth Warren sent letters Friday to four large infrastructure investors asking for information about their data center deals, according to Axios.

The Massachusetts Democrat, who serves as ranking member on the Senate Banking Committee, sent the letters to BlackRock (NYSE: BLK), Blackstone Group (NYSE: BX), Brookstone Infrastructure Partners and KKR (NYSE: KKR). Warren focused on potential overlaps between ownership of data centers and utilities, though she did not allege any wrongdoing.

The letters request information on investments in data center companies, including any changes to financial structure and operations, as well as investments in other companies in the data center supply chain.

Warren also asked the firms to provide documentation showing their efforts to mitigate regulatory risks that come with owning data centers. She requested an explanation of how the firms are ensuring that their presence in both energy supply and demand will not allow them to increase energy costs.

The requests come as energy prices rise and data centers that support artificial intelligence operations draw increased political attention. The firms either declined to comment or had not responded to requests for comment.