By Laura He, MarketWatch

HONG KONG (MarketWatch) -- Hong Kong stocks broke a four-day string of gains on Thursday, after a private survey showed China's manufacturing growth eased in August.

The "flash" version of HSBC's China Manufacturing Purchasing Managers Index dropped in August to 50.3 from July's final reading of 51.7, marking the lowest level in three months, according to data out on Thursday from HSBC and Markit.

The benchmark Hang Seng Index ended down 0.7%.

State-owned major banks fell across the board, with China Merchants Bank Co., Ltd. sliding 2.2%, Bank of Communications Co., Ltd. declining 1.7%, and both Agricultural Bank of China Ltd. and China Citic Bank Corporation Ltd. down 1.6%.

Index heavyweight China Mobile Ltd. fell 0.3%. The move came after state-run Xinhua News said the telecom had denied reported plans for massive layoffs involving 300,000 contract laborers. China Mobile's smaller rivals China Unicom Hong Kong Ltd. and China Telecom Corp. also said they had no immediate plans to cut jobs. Shares of China Unicom rose 0.8%, and China Telecom traded up 0.2%.

In Japan, the Nikkei Average advanced 0.9%, while the yen (USDJPY) weakened to Yen103.841 from Yen103.710 a day earlier. The broader Topix index also finished up 0.9%.

On the Chinese mainland, the Shanghai Composite Index closed down 0.4%.

In other Asian markets, Sydney's S&P/ASX 200 inched up 0.1%, while Seoul's Kospi Composite Index fell 1.4%.

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