Unbelievable queues at Beijing subway stations

Tens of thousands of Beijing commuters are being forced to queue for up to an hour morning and night by stepped-up subway station security imposed this week after several deadly attacks and ahead of the June 4 Tiananmen crackdown anniversary. China's capital is already notoriously crowded, with a population of 20 million people, and lines outside some stations stretched for dozens of metres at rush hour.