BOSTON — Aerosmith singer Steven Tyler says he has returned to the United States for medical care and the band is canceling the last four shows of its tour in South America.

Tyler said on social media Tuesday that he flew back to the U.S. on Monday night after a show in Sao Paulo, Brazil.

He says he is "not in a life threatening condition" but needs to deal with a medical issue "immediately" to maintain future scheduled performances.

The band has canceled two shows this month, in Curitiba, Brazil, and Santiago, Chile, and two shows next month, in Rosario, Argentina, and Monterrey, Mexico.

Tyler says he expects to make a full recovery.

Aerosmith, known for their hits Walk This Way, Sweet Emotion and Dream On, formed in Boston in 1971.