Malawi state media say President Bingu wa Mutharika was to be taken to South Africa for additional treatment after collapsing. He was rushed to a hospital in Malawi's capital, Lilongwe, after becoming ill on Thursday.

The government has not disclosed the nature of the illness, but diplomatic sources say the 78-year-old leader was suffering from a heart problem. Medical sources said Mr. Mutharika was unconscious.

In an interview with VOA, Vice President Joyce Banda asked Malawians “to stay in prayer and to stay united” as they pray for President Mutharika to recover quickly.

Banda also said she is praying that God protects and strengthens President Mutharika's family.

She did not provide details about his medical condition.

Mr. Mutharika was elected president of Malawi in 2004 and won a second term in 2009.

Critics of the president say he has become increasingly autocratic. Nineteen people were killed last July in anti-government protests.