The U.S. Justice Department issued a rare, private rebuke of Google this week, faulting the tech giant for failing to promptly turn over critical information to government officials who are investigating the search and advertising company for potential antitrust violations.

In a letter sent Monday, the department said Google had engaged in “unacceptable” delays since it received legal orders starting in October to turn over a tranche of evidence, including details involving executives, that shed light on the company’s business practices, according to two people familiar with the missive who requested anonymity to discuss a law-enforcement proceeding.

Officials have been probing Google since last year, and the wide range of records they have sought suggest an investigation that could ultimately touch on the tech giant’s dominant search engine, its lucrative advertising empire and its Android smartphone operating system, The Washington Post previously reported.

The full scope of what the department has requested is not clear. But Ryan A. Shores, the associate deputy attorney general who signed the letter, appeared to hint at potential legal action if Google fails to comply, the people familiar with the matter said. He gave Google a March 2 deadline and said the department would be “compelled to pursue other mechanisms” if Google does not respond on time, according to sources.

One of the options available to the Justice Department would be to ask a court to force Google to turn over relevant records in the document request, known as a civil-investigative demand.

The Justice Department declined to comment for this story.

Julie Tarallo McAlister, a spokeswoman for Google, said the company had already provided millions of pages of documents in response to the DOJ’s earlier question. “We have a long track record of cooperating with regulators and will continue working to show how our products create choice, and help millions of consumers and businesses across the country,” she said in a statement.

In its aggressive quest for evidence, the letter reflects the rising tensions — and high stakes — as Google faces off against regulators who are increasingly concerned about the size and power of Silicon Valley’s largest tech companies.

Abroad, Google has long withstood withering scrutiny from government officials who consider it to be too big and powerful. European regulators in recent years have issued billions of dollars of fines and other punishments alleging Google engages in anti-competitive tactics to protect its search, advertising and smartphone businesses.

U.S. regulators also probed Google on antitrust grounds, but ultimately decided against breaking up the company or issuing severe penalties in 2013. Its approach sparked years of criticism that Washington had been too weak on Big Tech, allowing the top firms in Silicon Valley to gobble up new start-ups, sap news publishers’ revenue and leave consumers with a worse experience online.

Leading the latest charge in Washington is the Justice Department, which issued one of its first legal orders in August. It required Google to turn over records “relating to our prior antitrust investigations in the United States and elsewhere,” according to a securities filing from Google’s parent company, Alphabet.

The probe is hardly the only regulatory threat the company faces: The Justice Department is also reviewing online platforms generally, seeking to determine whether Facebook, Google and other Silicon Valley companies are sufficiently regulated. In recent weeks, agency officials appeared to signal they are planning to recommend reforms to laws that spare popular web platforms from being held liable for harmful content posted by their users.

And Google faces further antitrust scrutiny in the states, where nearly every attorney general — led by Ken Paxton of Texas — has been scrutinizing Google’s sprawling corporate footprint since last year.

The states’ probe, which has focused largely on Google’s advertising empire, has recently expanded to include search and smartphones, according to three people familiar with the matter who were not authorized to discuss a law-enforcement investigation.

Google battled Texas over its decision to retain outside competition experts who had worked previously on behalf of the tech giant’s foes, including News Corp. Google initially sought to block the experts from viewing sensitive data about its business practices, believing they might later weaponize it on behalf of the company’s competitors. Both sides ultimately reached a settlement earlier this month, which is pending before a Texas judge.