Thousands of Vietnamese workers at a major footwear factory are on strike for the sixth straight day to protest a social insurance law.

Vietnam is hit by several hundred labor strikes a year mostly over poor working condition and low pay, but protesting a government policy is rare.

Several thousand workers began the stoppage last Thursday at the compound of the Taiwanese-owned Pou Yuen factory in southern Ho Chi Minh City. There is a heavy police presence.

Pou Yuen Vietnam, which employs more than 80,000 workers, is a subsidiary of Pou Chen Group. It makes footwear for companies such as Nike and Adidas.

Workers are protesting a new law, which comes into effect next year, requiring them to buy social insurance when they retire instead of getting a one-time payment.