DETROIT, April 15 (Reuters) - General Motors ( GM ) is

moving its headquarters deeper into downtown Detroit after

spending more than 20 years in its riverfront home at the

Renaissance Center, a person familiar with the matter said on

Monday.

A spokesperson could not immediately be reached to comment,

but the U.S. automaker has scheduled a press conference at 4:30

pm ET with CEO Mary Barra and Dan Gilbert, an owner of property

in downtown Detroit as well as the Cleveland Cavaliers National

Basketball Association team.