Gov. Robert F. McDonnell and Fairfax County economic development officials on Thursday said that a newly created, high-tech federal contracting company has chosen Northern Virginia over Maryland as its home.

McDonnell (R) and the Fairfax County Economic Development Authority announced that Engility Holdings, Inc., which will be a new publicly traded company, and subsidiary L-3 Services, Inc., which will be renamed Engility Corp, are investing $6.5 million in a corporate headquarters near Chantilly as part of a spinoff from L-3 Communications Corporation.

The Fairfax County Economic Development Authority and the Virginia Economic Development Partnership secured the project with a $350,000 grant from the Governor’s Opportunity Fund, according to press releases from the governor and the authority.

Virginia beat out Maryland for the project, which adds 50 new jobs to more than 300 already based in Fairfax County, officials said. The spin-off will employ 9,200 worldwide.

New York-based L-3 Communications Corp. announced last summer its intention to spin off Engility as a new, publicly traded government services company supplying systems engineering and technical assistance to the Department of Defense and other federal agencies, along with civil and international clients. At the time, the parent company estimated that the spinoff would have sales of about $2 billion.