Six other people, including Rambo's manager, were hurt when her bus crashed into a guard rail and embankment on Interstate 44 near Mount Vernon, Mo., CMT.com said.

Rambo, a famed singer-songwriter who lived in Nashville, was 74 when she died early Sunday. Her songs have been sung by Dolly Parton, Elvis Presley, Whitney Houston and Barbara Mandrell, among others.

Having begun her gospel music career at age 12, Rambo went on to pen more than 2,500 songs. She earned a Grammy Award in 1968 for her album, "The Soul of Me."

Rambo was also inducted into the Nashville Songwriters Hall of Fame in 2007 and was twice inducted into the Gospel Music Hall of Fame -- as a solo artist in 1982, and with her former husband Buck Rambo and their daughter Reba as the Rambos in 2001, CMT.com said.