Former Umno leader Khairuddin Abu Hassan has been hospitalised with a high fever.

His lawyer Matthias Chang told Malaysiakini that Khairuddin might be down with dengue fever.

"He was admitted to Kuala Lumpur Hospital today, with high fever. They suspect it might be dengue.

"We were told he can't have visitors. But tomorrow, the investigating officer will tell me whether I can see Khairuddin with his wife Umi Aida," Chang said via SMS.

Khairuddin is currently being held by police under the Security Offences (Special Measures) Act (Sosma) for allegedly sabotaging the country.

This is in relation to his police reports in Switzerland, London, New York, Singapore and Hong Kong on the 1MDB scandal.

Khairuddin was first arrested last Friday night at his home in Mont Kiara, under Section 124C of the Penal Code, for attempting to commit acts detrimental to parliamentary democracy.

He was then remanded for six days, from Saturday till Thursday.

However he was released early on Wednesday, only to be re-arrested soon after, under Sosma for allegedly violating Sections 124K and 124L of the Penal Code.

Sections 124K and 124L, respectively, deal with sabotage and attempting to sabotage the state.

Prime Minister Najib Abdul Razak, who conceived the state investment fund 1MDB, has said there is an international plot to topple him.

Before Khairuddin was hospitalised today, he was being held at the Dang Wangi district police headquarters, Chang said.