The wife of a detained Chinese lawyer set off on Wednesday on a march of more than 100 km from Beijing to Tianjin city, where she believes her husband is being held incommunicado, in a bid to force authorities to explain his arrest.

Lawyer Wang Quanzhang, who took on sensitive cases of complaints of police torture and defended practitioners of the banned Falun Gong spiritual movement, went missing in August 2015 during a sweeping crackdown on rights activists.

His wife, Li Wenzu, has since heard little about her husband's fate although authorities told her lawyer he had been detained. Neither Li nor the lawyer has been allowed to see him.