Google is making its first major layoffs by cutting employees across the board from DoubleClick, its newly acquired ad serving company.

Google (GOOG) confirmed a New York Times report that about 300 people will be laid off from DoubleClick’s U.S. offices. Shocked employees were crying in hallways on Wednesday as they learned their fate at DoubleClick headquarters in New York.

The search giant said it will also place some DoubleClick employees “in transitional roles,” but did not specify where. DoubleClick has about 1,200 U.S. employees and 1,500 worldwide. A Google spokeman said the job cuts only affected those acquired from DoubleClick and the company has no immediate plans to cut its own employees.

“As with many mergers, this review has resulted in a reduction in headcount at the acquired company,” a Google spokesman said in a statement. “We are confident that our combined organizational structure, along with the skills and experience of our new colleagues, will allow us to continue to offer great products and services to our customers.”

Layoffs were widely anticipated. When the $3.1 billion acquisition, Google’s largest ever, closed on March 11, CEO Eric Schmidt suggested that there would be layoffs as the two combined forces. Google announced its intent to buy DoubleClick a year ago.  

Google, which built its empire with search advertising, wants to aggressively move into the graphical advertising market with DoubleClick. Industry watchers have been waiting to see how Google and DoubleClick will alter the online advertising landscape. Last week, Attributor, which helps publishers track their web content, released new data on Google and DoubleClick’s dominance. Together, DoubleClick and Google commanded 70% of the ad server market share in January.