May 20 (Reuters) - Hong Kong stocks ended mixed on Wednesday, with the benchmark Hang Seng index sagging but an index tracking Chinese companies firmer, helped by strength in mainland stocks.
The Hang Seng fell 0.4 percent to 27,585.05 points, while the China Enterprises Index gained 0.3 percent to 14,235.90.
Trading in shares of China's Hanergy Thin Film Power Group was suspended after its stock plunged nearly 50 percent in less than one hour - a sudden and brutal decline after a long run-up in market value. The reversal left many analysts puzzled.
Among the most actively traded stocks on Hong Kong's main board were Nan Hai Corp, up 34.7 percent to HK$0.19 Harmonic Strait Financial Holdings Ltd, up 68.4 percent to HK$0.32 and CCT Land, down 3.2 percent to HK$0.03. (Reporting by Samuel Shen and Pete Sweeney; Editing by Kim Coghill)