Hong Kong's benchmark Hang Seng Index opened up 0.5% before falling 36 points in early trading on Wednesday. Other Asian markets were mixed as global bond yields and oil prices paused ahead of the US Federal Reserve's policy decision later today. The US 10-year Treasury bond yield was 0.8 basis points lower at 4.9875% in Asian trade, after breaching the 5% mark on Tuesday for the first time in three years. Traders believe a 25-basis-point hike from the Federal Reserve is almost assured, with the CME Group's FedWatch tool pricing a 92.4% probability. Brent crude futures slipped 0.6% to US$108.08 a barrel.