Pope Francis on Sunday was admitted to a hospital in Rome for a "scheduled" colon procedure, the Vatican said in a statement.
What do we know so far?
Francis was admitted to Gemelli Polyclinic "for a scheduled surgery for symptomatic diverticular stenosis of the colon." The intestinal disease can cause pain or fever in the elderly.
The Vatican did not say at what time Francis would undergo the procedure. More information will be released after the operation.
Francis possibly hinted at the surgery during a public appearance last Sunday.
"I ask you to pray for the pope, pray in a special way," Francis told fellow Catholics at St. Peter's Square on June 27. "The pope needs your prayers."
Does Francis suffer from any other health problems?
Francis is in fairly good health for his age, although he does a problem with his hip. He also suffers from pain along the sciatic nerve in the back and leg, a condition which is known as sciatica.
Francis had a part of his lung removed due to an infection while he was a young man.
The pope is still fit to travel, and is expected to visit Hungary and Slovakia in September.