Frank Sinatra, who was transported to Cedars-Sinai Medical Center by ambulance Tuesday, remained at the hospital Wednesday night, a hospital spokeswoman said.
The hospital would not comment late Wednesday on the 82-year-old entertainer's condition or prognosis.
At 9 a.m., Tuesday, Sinatra, accompanied by his wife, Barbara, was taken to the West Los Angeles hospital by ambulance, but without lights or siren.
A hospital spokeswoman said at the time that "he arrived in a nonemergency status." And, she added, he was undergoing some tests.
Sinatra had a heart attack a year ago, but the hospital would not comment Wednesday on whether his visit was related to a heart condition.