Former Israeli president Shimon Peres has suffered a stroke and has been rushed to hospital.
His office said doctors had sedated the 93-year-old and placed him on a respirator. Mr Peres, who is expected to undergo a CT scan, is reported to be in a serious condition.
Israeli TV stations, citing hospital officials, said Mr Peres was suffering from bleeding to the brain and described his condition as serious.
Earlier this year, Mr Peres was twice taken to hospital for heart problems but quickly released.
Mr Peres has held virtually every senior political office in Israel over a seven-decade career, including three terms as prime minister as well as stints as foreign minister and finance minister.
He won the 1994 Nobel Peace Prize for his work in reaching an interim peace agreement with the Palestinians.
As president, a largely ceremonial office, he cultivated an image as the country's elder statesman and became a popular fixture at international conferences such as the World Economic Forum in Davos.
Mr Peres has remained active since completing his seven-year term as president in 2014, and is one of the country's most popular public figures.
He often hosts public events at his peace centre, bringing together Arabs and Jews in efforts to promote peace and coexistence.
In a message posted on Facebook, Prime Minister Benjamin Netanyahu wished Mr Peres a speedy recovery.
"Shimon, we love you and the entire nation wishes you get well," he said.