KINSHASA, Congo (AP) — Officials say Congo’s longtime opposition leader Etienne Tshisekedi is seeking medical treatment in Belgium.

The 81-year-old political figure reportedly has been suffering complications from diabetes in recent months.

In a statement Saturday, Tshisekedi’s political party said he would be convalescing abroad but offered no further details.

Tshisekedi lost the 2011 presidential election to incumbent leader Joseph Kabila, and later contested the results.

He has long battled rumors of ill health. In 2010, he walked the 15 miles (25 kilometers) from the airport to his suburban home in Kinshasa upon his triumphant return from medical treatment abroad.

Tshisekedi formed Congo’s first opposition party in 1982 to combat the longtime dictatorship of Mobutu Sese Seko.

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