BEIJING, Oct. 21 (Xinhua) -- War epic film "The Battle at Lake Changjin" continued leading the Chinese mainland box office on Wednesday, figures from the China Movie Data Information Network showed on Thursday.

With a daily revenue of 41.5 million yuan (about 6.5 million U.S. dollars), the film's total box office sales topped 5.05 billion yuan on Wednesday after 21 days of screening.

Another film of patriotic theme, "My Country, My Parents," stayed second on the chart, finishing the day with 9.64 million yuan.

In third place was domestic comedy thriller "Knock Knock," which pocketed 1.47 million yuan in presale. The film is scheduled to hit cinema screens on Friday. Enditem