News at Seven-Thirty highlights: Police are holding four teenage boys for attempted taxi robbery and assault; Hong Kong today confirmed four more cases of H1N1 infections; a suspected flu patient left the hospital without approval; new policies have stepped up to fight against H1N1 flu in China; rescuers in Chongqing are racing against time to try to free 27 miners trapped underground; Barack Obama promised a new and stronger response to defiant North Korea; police have released on bail three teenage girls suspected of drug abuse and possession of drugs; Christian Zheng Sheng College has won government’s support for relocating to Mui Wo; a fire broke out at a container storage yard in Tin Shui Wai; a HK resident has started the Project Kaiser to study plastic vortexes in the Pacific.