FORT CAMPBELL, Ky. (AP) - When Sgt. Asan Akbar was taken into custody for allegedly killing a fellow serviceman with a grenade, an Army spokesman said he may have acted out of resentment. But where such bitterness may have come from remains a mystery.

Akbar had reportedly told his mother he feared persecution because he is a Muslim and been reprimanded recently for insubordination. The deadly attack also wounded 15 other soldiers Sunday, three seriously.

The woman who said she is Akbar's mother, Quran Bilal, told The Tennessean of Nashville that she was concerned her son might have been accused because he is a Muslim. She said he was not allowed to participate in the first Gulf War because of his religion.

''He said, 'Mama, when I get over there I have the feeling they are going to arrest me just because of the name that I have carried,''' Bilal told the newspaper for a story published on its Web site Sunday night.

Akbar, of the 101st Airborne Division's 326th Engineer Battalion, was in custody, said George Heath, a civilian spokesman at Fort Campbell. Heath said Akbar had not been charged with a crime but was the only person being questioned in the attack.

Jim Lacey, a correspondent for Time magazine, told CNN that military criminal investigators said Akbar was recently reprimanded for insubordination and was told he would not join his unit's push into Iraq.

Heath also said Akbar had been having ''an attitude problem.''

The motive in the attack ''most likely was resentment,'' said Max Blumenfeld, another U.S. Army spokesman.

Bilal said from her Baton Rouge, La., home that the military had not contacted her and expressed disbelief in the accusations against her son, who she said spells his first name Hasan.

''He wouldn't try to take nobody's life,'' she said. ''He's not like that. He said the only thing he was going out there to do was blow up the bridges.''