Democratic presidential candidate U.S. Rep. Tulsi Gabbard (D-HI) speaks during the AARP and The Des Moines Register Iowa Presidential Candidate Forum on July 17, 2019 in Cedar Rapids, Iowa.

Democratic presidential candidate Rep. Tulsi Gabbard of Hawaii is suing Google, alleging the company unfairly suspended her campaign ads.

Gabbard's campaign organization Tulsi Now, Inc. filed a lawsuit on Thursday in a federal court in Los Angeles, claiming Google suspended the campaign's advertising account for six hours on June 27 and June 28, which disabled efforts to raise funds and reach potential voters. The lawsuit also alleges campaign emails were placed in spam folders on Gmail at "a disproportionately high rate" compared with emails from other Democratic candidates.

The suit comes as lawmakers and politicians from both sides of the aisle increase scrutiny of Big Tech. This week, the U.S. Department of Justice publicly announced it is probing large tech companies. Google's search business has been highly scrutinized by politicians and industry competitors alike.

A Google spokesperson said in a statement that Gabbard's account suspension was a result of the company's automated systems.

"We have automated systems that flag unusual activity on all advertiser accounts — including large spending changes — in order to prevent fraud and protect our customers," the Google spokesperson said in a statement to CNBC. "In this case, our system triggered a suspension and the account was reinstated shortly thereafter. We are proud to offer ad products that help campaigns connect directly with voters, and we do so without bias toward any party or political ideology."

"Google's discriminatory actions against my campaign are reflective of how dangerous their complete dominance over internet search is, and how the increasing dominance of big tech companies over our public discourse threatens our core American values," Gabbard said in a blog post Thursday.

"This is a threat to free speech, fair elections and to our democracy, and I intend to fight back on behalf of all Americans," Gabbard added.

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