ADDIS ABABA, Ethiopia — Ethiopia’s state television said Prime Minister Meles Zenawi, the East African nation’s longtime ruler, has died. He was 57.

Authorities did not immediately announce the cause of his death, but Meles had not been seen in public in Ethiopia in weeks. State TV announced the death on Tuesday. It said Meles died Monday after contracting an infection. Recent images of Meles aired by Ethiopian Television showed him noticeably thinner.

State TV said the country’s deputy prime minister, Hailemariam Desalegn, was put in charge of the Cabinet.