Cameron upset as Hong Kong erupts in pepper spray, batons

Protesters and police again clashed in Hong Kong today as hundreds of demonstrators tried to surround government offices.

It is some of the worst trouble in two months of pro-democracy protests, with police using pepper spray and batons. Police say 40 people have been arrested and a number of officers were injured.

Meanwhile, Britain's Prime Minister David Cameron said he believes a Chinese decision to prevent a committee of British members of parliament from visiting Hong Kong is mistaken, and has only served to heighten concerns around the former British colony.

China on Sunday barred British MPs from entry to Hong Kong to undertake research related to an inquiry about progress towards democracy.

Cameron's spokesman sharply criticised that decision today, escalating a diplomatic dispute that threatens to damage relations between London and Beijing at a time when economic and trade ties between the two are becoming closer.

'No' to Beijing-run regime

The demonstrators are calling for the right to choose their leader without interference from China. Hong Kong used to be run by Britain until 1997, but it is now under Chinese control.

The protests are over the upcoming election of Hong Kong's next leader, or chief executive, which are scheduled for 2017.

China has promised that everyone in Hong Kong will be allowed to vote in that election - something that hasn't happened before. But it has also said it wants the final say on who can run to be leader.

The protesters, a bulk of them students, aren't happy - they want to be able to decide their leader in free and fair polls, without any interference from Beijing.