HONG KONG — As China’s global political and economic clout has grown, its government has moved beyond silencing critics at home to blocking scrutiny of its human rights record around the world, an advocacy group said on Tuesday.

Human Rights Watch, a New York-based group, outlined the moves in a global report on repressive governments that said Beijing stood out in the boldness of its attacks on critics around the world.

“No other government flexes its political muscles with such vigor and determination to undermine the international human rights standards and institutions that could hold it to account,” wrote Kenneth Roth, the organization’s executive director.

The group says its own recent experience is a case in point. Mr. Roth was barred on Sunday from entering Hong Kong, a semiautonomous Chinese territory normally regarded as a bastion of free speech in the region, where he had planned a news conference.