Raytheon Co. said Wednesday it bought privately held cybersecurity company Blackbird Technologies for about $420 million.

Raytheon, a defense contractor based in Waltham, said the acquisition will help expand its surveillance and cybersecurity services to clients. Blackbird, based in Herndon, Va., has customers in the defense, intelligence, and law enforcement industries.

''Blackbird expands Raytheon's already-established footprint in the intelligence community market while helping to grow our cyber operations and special missions support to the Department of Defense,'' Lynn Dugle, president of Raytheon's intelligence information and services unit, said in a statement.

Associated Press