A US military service member and his family were injured in the Brussels attacks

The US military says one American service member and his family were injured in the Brussels attacks.

US European Command says it will not release details of the injuries or the number of family members involved, due to privacy concerns. The command says that it is continuing to confirm the safety of US military personnel and families in the region, including those who may be there on vacation or official travel.

The US Department of Defense issued a statement to CBS news stating: ""One US service member and his family who were caught up in this tragedy. Due to privacy concerns, we are not releasing the status of their injuries at this time."

And CBS reports that the Defense Department and the US Embassy expect that the number of Americans affected by the attack will continue to climb, as there are a number of Americans who live, work, and travel in Belgium.

So far at least four Americans were hurt in the explosions that ripped through the Brussels Airport and a metro station Tuesday. Mormon church officials said three missionaries from Utah were seriously injured in the airport attack and have been hospitalized.

In response to the attacks, the US Embassy in Belgium has issued a Level 4 threat rating, which corresponds to a "serious or imminent attack."

"The US Embassy recommends sheltering in place and avoiding all public transportation. We will update with further information when available," the embassy wrote in an online statement.

The Islamic State militant group has claimed responsibility for the attack.

(Associated Press reporting by Lolita C. Baldor)