Former US President George H.W. Bush has been admitted to a hospital here, where the 92-year- old leader is responding to treatment, his top aide said on Wednesday.
Bush was admitted to Houston Methodist Hospital falling ill recently.
"He's there. He's fine and he's doing really well," Bush's chief of staff, Jean Becker was quoted as saying by Houston Chronicle newspaper.
She said the doctors have a couple of theories about Bush's condition, but he is responding to treatment.
Becker did not specify the reason why Bush was hospitalised.
Bush, who lives in Houston, Texas, is expected to be discharged in the next couple of days, the report said.
Bush served as America's 41st president from 1989 to 1993.
As is the case with most people his age, Bush has had his share of health issues in recent years.
In July 2015, he was taken to a hospital in Portland, Maine, after he fractured a bone in his neck in a fall at the family's summer home in Kennebunkport. He was "up and talking and out of bed" within a day after the fall.
The fall happened about six months after he was taken by ambulance to Houston Methodist for what his spokesman called "shortness of breath." He was released from the hospital about a week later.
In late 2012, Bush was admitted to the hospital for a bronchitis-related cough. He was later released but returned the day after Thanksgiving because of a persistent cough. Bush was later admitted to intensive care and spent nearly two months at the hospital until his release in mid-January 2013.