Singer, wife, two band members died Sunday.

Country singer and Grand Ole Opry star Billy Walker was killed along with his wife and two band members early on Sunday when the car they were traveling in ran off an interstate highway and overturned south of Montgomery, Alabama, state highway troopers said.

The popular 77-year-old Walker, whose biggest hit was "Charlie's Shoes" on CBS Records, joined the Grand Ole Opry in 1960 and had performed ever since in concerts and on TV shows.

Also killed were his wife, Bettie Walker, 61, and band members Charles Lilly, 44, and Daniel Patton, 40, all of Tennessee.

Walker's grandson, Joshua Brooks, 2l, was hospitalized in critical condition.

They were returning to Nashville after performing at a club near Gulf Shores, Alabama.