Hong Kong, June 24 -- Protesters fearing an erosion of Hong Kong's legal autonomy blocked access to a government office building for nearly two hours Monday and plan more demonstrations to draw the attention of leaders attending the G-20 summit this week.

About 100 demonstrators jammed the entryway and lobby of the Inland Revenue Tower, a skyscraper in the Wan Chai district in the city center.

Earlier, one of the main protest groups announced a demonstration planned on Wednesday to try to draw the attention of world leaders attending the Group of 20 summit in Japan.

The leaders of the Civil Human Rights Front said they hope the world leaders meeting in Osaka will hear the protesters' concerns over the weakening of the city's legal auto...