China is urging fresh efforts to curb unpaid wages among its vast and increasingly disgruntled migrant work force, as the government braces for a seasonal surge in labor unrest ahead of the Lunar New Year.

The problem is a perennial one among China’s 274 million migrant workers, but Beijing is particularly anxious this year. Slowing economic growth has fueled a dramatic rise in labor unrest, particularly in the once-booming construction and manufacturing sectors.

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