Facebook served up nearly a third of the 1.11 trillion display ads delivered to US Internet users in the first three months of this year, industry tracker comScore said on Wednesday.

Facebook was the stage for 346 billion "impressions," or views, of display ads in a near doubling of the number seen in the same quarter a year earlier, according to comScore.

"The US online display advertising market maintained its strong momentum from last year with a terrific first quarter," said comScore executive vice president Jeff Hackett.

"We are now seeing more than one trillion display ads delivered every single quarter and nearly 300 individual advertisers spending at least $1 million a quarter on display."

Facebook.com was the top spot for online display ads, with its share growing to 31.2 percent of the market from 16.2 in the same quarter last year, according to comScore.

Yahoo! websites ranked second with 112 billion impressions, followed by Microsoft, AOL, and Google in that order. Google still dominated in the lucrative market for texts ads posted with search results.