Northrop Grumman Corp. yesterday completed its $5.1 billion purchase of Litton Industries Inc., creating one of the defense industry's most diverse conglomerates and establishing itself as one of the biggest employers in the Washington area.

With 16,400 employees in facilities from Northern Virginia to south of Baltimore, Northrop Grumman is now the largest non-retail, for-profit employer in the Washington region, just ahead of Verizon Communications Inc.

Corporate headquarters are in Los Angeles, but two of Northrop Grumman's three operating divisions are located near the District: the Electronic Sensors & Systems Sector is in Linthicum, near Baltimore-Washington International Airport, and the Logicon Inc. information technology sector is based in Herndon.

The company's new bulk in the information technology market -- rolling former Litton units PRC and TASC into Logicon -- creates an imposing competitor for other local contractors, said Brett Lambert of DFI International, a consultant to defense contractors.

"Before, these companies were all kind of princes, and now all of a sudden there's a king in town," Lambert said.

The consolidation also makes Northrop Grumman -- maker of the B-2 stealth bomber -- into a shipbuilder, with the addition of Litton's Ingalls shipyard in Mississippi and its Avondale shipyard in New Orleans. Finally, the deal adds new lines of business in military electronics, buttressing the company's recent efforts to transform itself from an airplane builder into an innovator in "cyber warfare."

"Without question, the global military environment has changed. . . . With Litton, we have solidified our position in major growth segments of the 21st century defense marketplace," Kent Kresa, Northrop Grumman chairman, president and chief executive, said in a news release.

Northrop Grumman paid $3.8 billion in cash and assumed Litton's debt of $1.3 billion. The combined company will have 80,000 employees worldwide and annual sales of $15 billion.

Announced just before Christmas last year, the deal cleared U.S. and European regulatory review relatively quickly, Lambert said, because there was so little overlap between the two companies.

Staff writer Terence O'Hara contributed to this story.