Eswatini’s main opposition leader was poisoned in an assassination attempt, his party claimed Wednesday. It is one of the last remaining absolute monarchies and where authorities have for years moved to quash pro-democracy movements.

The People’s United Democratic Movement party (PUDEMO) said its president, Mlungisi Makhanya, was hospitalized after being poisoned in neighboring South Africa on Tuesday.

Makhanya had recently said there would be new pro-democracy protests in Eswatini next month.

Eswatini government spokesperson Alpheous Nxumalo denied any involvement.

King Mswati III rules Eswatini, a country of 1.2 million, with power over all branches of the government. The 56-year-old has been king since he succeeded his father in 1986 at the age of 18.