Washington (CNN Business) Texas's attorney general has sent the privacy-focused search engine DuckDuckGo a demand for documents and records as part of a multi-state antitrust probe into anti-competitive behavior by Google (GOOG).

The legal request — a copy of which was obtained by CNN — was sent to DuckDuckGo earlier this month. It asks DuckDuckGo to reproduce any information it has provided to the Justice Department in connection with the federal agency's own Google antitrust probe.

The move highlights the broad reach of investigators as 50 attorneys general , led by Texas Attorney General Ken Paxton, probe Google's business for wrongdoing. It underscores how investigators are increasingly seeking testimony from businesses that compete with Google for market share.

In September, Texas kicked off the investigation by sending Google its own civil investigative demand, which CNN also obtained. With more than 200 numbered questions, the demand asked Google to explain its past mergers, its advertising technology and its data collection practices, among other things. A civil investigative demand, or CID, carries the weight of a subpoena.

DuckDuckGo acknowledged the CID it received in a statement to CNN on Wednesday, saying that it intends to cooperate with the investigation of Google.

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