Attorneys general from 48 US states, the District of Columbia and Puerto Rico have formally opened an antitrust probe into Google, in a sign of growing government scrutiny of technology giants.
New York-based technology analyst Ryan Patel told Euronews the action was the first of its kind against the tech sector.
“When you can get both the Republicans and Democrats to come together to agree on something, it is pretty significant.”
Texas Attorney General Ken Paxton, who is leading the probe, said it would focus on Google's "overarching control of online advertising markets and search traffic that may have led to anti-competitive behaviour that harms consumers".
California and Alabama declined to be part of the probe.
Several Attorneys General present at the announcement in Washington described the investigation as "preliminary" and said they expected it would expand to cover other issues, including data privacy.
A separate group of eight state attorneys general, led by New York, joined by the District of Columbia, announced on Friday it was investigating Facebook.
The attorneys general declined to say if they planned to expand scrutiny to other large tech firms.
Arkansas Attorney General Leslie Rutledge called Google's search engine a "juggernaut" and argued that a free search sometimes came at the cost of the freedom to choose the best products from the best companies.
Tech giants that were once praised as engines of economic growth have increasingly come under fire for allegedly misusing their clout and for lapses such as privacy breaches.
Specifically, Google faces accusations that its web search leads consumers to its products to the detriment of rivals'.
There have also been complaints of potentially anti-competitive behaviour in how it runs the advertising side of its business.