Brazil President Jair Bolsonaro was on Wednesday admitted to hospital after a prolonged case of hiccups, the government said. The doctors will try to investigate the cause of persistent hiccups, which have been there for 10 days.

The 66-year-old far-right leader had been complaining publically since last week that he had been suffering from hiccups after a dental implant surgery on July 3.

He has been taken to a military hospital in the capital Brasilia. There he will undergo tests in order to ascertain the cause of the hiccups, according to a statement issued by the presidential palace.

“He is in good spirits and feels well,” said the presidency, adding that Bolsonaro would remain under observation for the next 24-48 hours, although “not necessarily in hospital.”

Speaking to a local radio station last week, Bolsonaro had said: “This happened to me before, maybe due to the medicine I’m taking, I have hiccups 24 hours a day.”

On Tuesday night, a tired-looking Bolsonaro had complained to supporters outside his official residence in Brasilia about the problem.

“People, my voice has gone. If I start talking a lot, the hiccups return … they already have,” he said.

After being stabbed on the campaign trail in September 2018, Bolsonaro has undergone several surgical procedures on his abdomen since he was elected.

He also contracted Covid-19 last year although his symptoms were mild and he did not need hospital treatment.