(CNN) The Department of Defense has identified three of the four Americans killed in Syria on Wednesday, and the fourth, a contractor, was named by her company.

Army Chief Warrant Officer 2 Jonathan R. Farmer, 37, of Boynton Beach, Florida; Navy Chief Cryptologic Technician Shannon M. Kent, 35, of upstate New York; and DOD civilian Scott A. Wirtz of St. Louis, Missouri were killed Wednesday in the explosion in Manbij, Syria, according to the Department of Defense.

All three died "as a result of wounds sustained from a suicide improvised explosive device," according to the military.

The fourth individual was identified in a statement from a spokesperson for her company, Valiant, as Ghadir Taher of East Point, Georgia.

"We are extremely saddened by the tragic and senseless passing of Ghadir Taher. ... She was a talented and highly-respected colleague loved by many who will be dearly missed," said Tom Becker, the head of the New York office for Sitrick and Co., which does public relations for Valiant.

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