Top generals who had supported Yemen’s former leader and a rebel uprising switched their allegiance to the government in exile, the first sign that renegade military units crucial to the rebellion are returning to state control.

Although key military units still remain loyal to former President Ali Abdullah Saleh—a long-serving autocrat who was overthrown by popular revolt in 2012—Thursday’s defections represent a heavy blow to the former president and his Houthi allies in their campaign against pro-government forces.

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