Yemeni officials say a suicide bomber killed at least 20 people when he blew himself up in the middle of a group of soldiers practicing for a military parade.

Officials said Monday's attack in the capital, Sanaa, wounded scores of others. The soldiers were preparing for a parade on Tuesday to mark Yemen's unification of the north and the south.

No one has claimed responsibility for the attack.

Yemen is home to al-Qaida in the Arabian Peninsula, which is known as one of the terrorist group's most dangerous offshoots.

Separatists in Yemen's south also target the military.