Fort Bragg, N.C. — A Fort Bragg soldier charged with having explosives in his carry-on luggage at a Texas airport was stopped earlier at Fayetteville Regional Airport when security screeners found a military grenade in his bag, according to the FBI.

Trey Scott Atwater, 30, was stopped at security at the Midland International Airport in Texas on Saturday after a Transportation Security Administration officer spotted a suspicious item in a carry-on bag during X-ray screening.

According to an FBI affidavit in the case, the material was C-4 plastic explosive. Officers found no detonator, meaning there was no way to ignite the explosive.

Atwater flew out of Fayetteville on Christmas Eve, and security there detained him after finding a military smoke grenade in the bag, the FBI affidavit states. TSA agents in Fayetteville didn't see any C-4 in the bag at the time, according to the affidavit, and they allowed Atwater to continue on the flight to Midland after confiscating the grenade and admonishing him.

Despite that incident, Atwater told FBI agents that he didn't know the explosives were in the bag, which he said he brought home from Afghanistan last April, according to the affidavit.

An instructor at the John F. Kennedy Special Warfare School at Fort Bragg, Atwater said his 7th Special Forces Group team routinely carried at least two blocks of C-4 on any operation, the affidavit states. Since he was a demolitions expert, he often carried more, he told investigators.

Yet, he said, he hadn't used the bag since returning from deployment and only grabbed it from the garage of his Hope Mills home to carry children's items on a family trip to Texas over the holidays, the affidavit states. He expressed surprise that the C-4 was found inside.

Atwater was being held at the Midland County jail on a charge of trying to bring explosives onto an airplane.

Army officials say he is likely to face military discipline, in addition to the federal charge.