Artist Yoko Ono has been admitted to hospital in New York with “flu-like symptoms”, her spokesperson says.
But Elliot Mintz denied reports she had suffered a stroke.
He said she went to hospital on the advice of her doctor and was expected to be discharged and return home later on Saturday.
Ono, 83, was married to former Beatle John Lennon until he was murdered in 1980 outside New York’s Dakota Building, where she still lives.
An ambulance was called to the building at 21:00 on Friday (02:00 GMT Saturday), a Fire Department spokesman said.
Ono is spending the night in Mount Sinai Roosevelt Hospital in Manhattan.
She’s “OK, and she should be home tomorrow (Saturday)” said Mintz, after speaking to someone with her at the hospital.
Her son Sean Ono Lennon also tweeted that his mother was doing well, reports the BBC.