Hong Kong's stock market dropped Thursday, giving up its gains from the previous session as investor hopes dwindled for government measures to boost China's markets.

The blue-chip Hang Seng Index fell 539.2 points, or 2.6 percent, to 20,392.06.

Hong Kong stocks jumped Wednesday along with mainland bourses on speculation, fueled by comments from investment bank JPMorgan, that Beijing might intervene to prop up the country's ailing markets.

With no word from China's central government on Thursday, many investors decided to book profits.

"I think you can't hang on to hope more than 24 hours in this market," said Benjamin Collett, head of hedge fund sales trading at Daiwa Securities SMBC Co.

Chinese airlines saw big declines, with China Southern losing 4.6 percent to HK$2.5 and China Eastern off 7.1 percent to HK$1.56.

Billionaire Li Ka-shing's companies -- conglomerate Hutchison Whampoa Ltd. and developer Cheung Kong (Holdings) Ltd. -- also fell. Both reported better-than-exepcted earnings Thursday.

Hutchison shed 1.3 percent to HK$70.55 on Thursday. Cheung Kong slid 2.79 percent to HK$101.1.

Firmer crude prices pushed PetroChina and Sinopec lower, but buoyed upstream oil producer CNOOC by 0.6 percent.