Clashes at Hong Kong Polytechnic University as police warn of lethal force

Hong Kong has witnessed some of the most severe violence in its months-long series of protests.

As police attempted to clear Hong Kong Polytechnic University with tear gas, armoured cars and water cannon, protesters responded with petrol bombs, arrows and other missiles, some of them fired from large catapults.

Armed police have warned they may use lethal force to clear the site.

Earlier, the police offered to allow people in the site to leave, only to arrest many of those who did not have official press accreditation.