LOS ANGELES (Reuters) - Alicia Keys has canceled two shows on her newly launched North American tour because of swollen vocal cords, her record label said on Wednesday.

The 27-year-old R&B singer scrapped Tuesday's show in Pittsburgh, the third stop of the tour, and has also pulled the plug on Thursday's concert in Cleveland.

The tour is expected to resume in Columbus on Saturday. Tickets for the Cleveland show will be honored at Columbus, said J Records.

Keys' tour, to promote her chart-topping album "As I Am," began last Saturday in Hampton, Va.

Sore throats must be contagious on the tour. One of Keys' opening acts, 2007 "American Idol" winner Jordin Sparks, has been unable to perform because of an acute vocal cord hemorrhage. Her Jive Records label expected her to join the trek in May.

Dates are on tap through June 18 at Madison Square Garden in New York City.

Source: Reuters/Nielsen