DETROIT — Levi Stubbs, the gravelly-voiced, imploring lead singer of the Motown group the Four Tops, who stood out in 1960s pop classics like “Reach Out, I’ll Be There,” and “Bernadette,” died on Friday at his home here. He was 72.

His death was confirmed by the office of the Wayne County Medical Examiner. No cause was given. Mr. Stubbs had had a series of illnesses, including a stroke and cancer, that forced him to stop performing in 2000, although he briefly participated in the Four Tops’ 50th-anniversary concert in 2004, which was broadcast on public television.

Formed while its original members were in high school, the Four Tops were one of the most successful groups of the 20th century. They had more than 40 hits on the Billboard pop charts, including their first No. 1 single, “I Can’t Help Myself (Sugar Pie, Honey Bunch)” in 1965.

Hugely popular abroad as well as in the United States, the group became a linchpin of Motown Records, the Detroit label started by Berry Gordy Jr., and was second only to the Temptations, with whom it was often compared, in popularity among its male artists. In 1990 the Four Tops were inducted into the Rock and Roll Hall of Fame.