HOUSTON - The wife of a U.S. Army officer serving in Afghanistan witnessed her husband's death as the two video chatted via Skype, his family said Friday.

The circumstances of Capt. Bruce Kevin Clark's death were not immediately available. The Pentagon said it was under investigation, and his brother-in-law said he didn't have details.

"We are entrusting the military with investigating and with finding out what happened to Capt. Clark," Bradley Taber-Thomas told The Associated Press.

Clark, a 43-year-old Army chief nurse, grew up in Michigan and lived previously in Spencerport, New York, a suburb of Rochester and his wife's hometown. He joined the Army in 2006 and was stationed in Hawaii before he was assigned to the William Beaumont Army Medical Center in El Paso, Texas. He deployed to Afghanistan in March.

Taber-Thomas said in a statement that Clark died Monday while talking to his wife during one of their regular Skype sessions.

At the time of the incident, the family was hoping for a rescue and miracle, but later learned that it was not to be," he said. "Although the circumstances were unimaginable, Bruce's wife and extended family will be forever thankful that he and his wife were together in his last moments."

Clark's body was returned Thursday to Dover Air Force Base.

A funeral is planned in Spencerport, but details were not immediately available. Clark and his wife moved there in 2000. Military records show he was already a nurse when he joined the Army six years later.

He received a number of awards and decorations for his service.

"When you were in Bruce's presence it was apparent he served a higher purpose," Taber-Thomas said. "He was deeply honoured to serve his country, and he paid the ultimate sacrifice to serve people, his children, family, community, and church."

A memorial service also was planned in Addison, Michigan, where Clark graduated from high school.

"While we understand the interest our family's tragedy will attract given the unique circumstances, we ask that our privacy be respected during our time of grief," Taber-Thomas said.

Clark is survived by his wife and two daughters, age 3 and 9, he said.