The top anti-graft body in China, which is pushing for the extradition of corruption suspects who have fled abroad, condemned "some people" who protect corrupt officials in the name of human rights but did not name the targets of its ire.
China has sought increased international cooperation in its "Fox Hunt" campaign to track down officials and business executives suspected of corruption who have fled overseas.
But Western nations have been reluctant to sign extradition treaties with China, where mistreatment of criminal suspects remains a problem, and courts are not independent of the ruling Communist Party. They say China has not provided sufficient proof of suspects' crimes.
"Some people internationally use human rights and the law as excuses," the Central Commission for Discipline Inspection said in an online statement on Sunday. "Objectively they are providing shelter to corrupt elements."
Last week, the government said a man on its list of 100 most wanted corruption suspects abroad had voluntarily returned from Canada, where he had fled in 2011.
Chinese President Xi Jinping has waged a years-long campaign against graft that has felled hundreds of officials at all levels of government, including many of his top political rivals.