Officials revealed details Tuesday on at least nine Americans wounded in the deadly explosions at the Brussels airport and a subway station in the city, with one of the victims identified as a U.S. Air Force officer.

The unnamed officer and five of his relatives were wounded and "some are critical," a defense official told Fox News. U.S. officials told The Associated Press the officer is a lieutenant colonel.

"Our priority at this time is the safety and well-being of our airmen and their families," Secretary of the Air Force Deborah Lee James told reporters. U.S. European Command said it would not release details of the service member's injuries due to privacy concerns.

Mormon church officials said three missionaries from Utah were seriously injured in the airport attack and have been hospitalized. A fourth wounded missionary is a French woman.

State Dept. spokesman John Kirby says investigators are still working on a final count of all the Americans who were hurt.

The Church of Jesus Christ of Latter-day Saints issued a statement Tuesday identifying the three American missionaries as 66-year-old Richard Norby of Lehi, 20-year-old Joseph Empey of Santa Clara and 19-year-old Mason Wells of Sandy. They were near the explosion when it occurred and have been hospitalized.

Empey's family said in a statement, "We have been in touch with him and he is grateful and in good spirits... We are thankful for the outpouring of love and prayers from throughout the world, and we pray for all those affected by this tragedy."

The three American missionaries were serving in Paris and were at the airport with the fourth missionary who was on her way to an assignment in Cleveland, Ohio. That 20-year-old missionary, Fanny Rachel Clain, is from Montelimar, France.

She had passed through security at the time of the explosion. The church said she didn't make her flight out and has been hospitalized. It instructed others in the France Paris Mission to stay in their homes.

Wells' family said in a statement Tuesday night he has undergone surgeryto repair his Achilles heel, in addition to being treated for burns and shrapnel injuries.

"We are grateful that our son, Elder Mason Wells, survived the attack and is receiving quality medical care," the statement read. "We have spoken to him briefly and he feels blessed that he wasn’t injured more given his close proximity to the bomb."

At least 34 people were killed and nearly 250 wounded Tuesday after bombs went off in the Brussels airport. The Islamic State militant group has claimed responsibility for the attack.

"We are also working closely with our interagency partners and host nation counterparts to determine the appropriate steps to ensure the safety and security of all U.S. personnel," Air Force Lt. Col. David S. Westover, Jr. told reporters. 

The governor of Utah offered support to local families. Gov. Gary Herbert praised the Utah natives as "people of faith who have forsaken everything -- family, friends, school and careers -- in order to share a message of hope and love with the world."

Thousands of Utah Mormons have served proselytizing missions around the world. Church members account for as many as two-thirds of the state's population.

Fox News' Lucas Tomlinson and The Associated Press contributed to this report.