WASHINGTON — A suspect was in custody Monday after an American diplomat was found dead at home while serving in Madagascar.

State Department spokeswoman Heather Nauert said the death was being investigated by U.S. and local authorities.

She said the U.S. foreign service officer was found dead during the overnight hours Friday in the capital of the Indian Ocean nation off the east coast of Africa.

Nauert declined to identify the diplomat or release details on the circumstances of the death.

"A suspect is currently in custody," Nauert said.