BEIJING, March 17 (Xinhua) -- More than 180 museums across the nation have reopened after month-long closures amid efforts to curb the spread of the coronavirus, according to a release published Tuesday by the National Cultural Heritage Administration.

Continuing precautions for epidemic control, these museums asked visitors to make online appointments and pledged to limit the total number of visitors, stagger visiting periods and offer digital tour services to avoid public gatherings, the release said.

The Chinese health authorities said Tuesday that it received reports of 21 new confirmed cases of novel coronavirus infection, 20 of which were imported cases, on the Chinese mainland on Monday.