"Currently, there is no timetable for his return," the team said in its statement. "Hornets associate head coach Stephen Silas will serve as acting head coach. Out of respect for Clifford's privacy, the Hornets will have no further comment at this time."
Clifford has served as the head coach of the Hornets since the 2013-14 season, leading the team to a 169-181 record and two postseason appearances. Charlotte has started this season 9-13.
Tim Bontemps of the Washington Post and Zach Lowe of ESPN.com spoke highly of Clifford while wishing him well:
Silas has been a longtime assistant in the NBA, coaching for the Hornets/New Orleans Pelicans (2000-03), Cleveland Cavaliers (2003-05), Golden State Warriors (2006-10) and the Charlotte Bobcats/Hornets (2010-present).