According to the a Guardian UK report, protestors claim that things turned violent when police blocked a permitted march near the convention center. Tear gas, water cannon, pepper spray and electric baton use have been reported, and used in excess and a number of bystanders were affected. As of 3:30am Sunday (Hong Kong time), mass arrests are being reported with over 900 protests surrounded at the convention center site and being bused out slowly, there is also an unconfirmed report that one protestor has died in hospital but no other media sites seem to substantiate this claim as of yet [Update: It seems this report may have been about a protestor in South Korea from previous protest, read more here]. NotoWTO Blog has breaking updates from the crowd being arrested at the convention center site which I'll reprint below. Labourstart's Global newswire has several related stories as does Guy Taylor's dispatches from Globalize Resistance. Here's a general overview from monters and critics. Target WTO's news stream is also up to date, here's their latest:
There are also links to video and timelines of other events and protests at the target WTO site. Also, here's a link to a CNN video on today's protest.
Dec 17th, HK:
(i) Pakistan's Commerce Minister and
facilitator Humayun Akhtar Khan  has stated "no breakdowns or breakthroughs" had occurred during the WTO talks, although with news circulating that no new agreement may be signed,  the International League of Peoples' Struggle (ILPS) are now preparing for a "celebratory mass action" tomorrow.
(ii) Big protests took place in the evening, reports say people were confronted with a large police
presence. The police used a lot of pepperspray to try and disperse people.
(iii) Hong Kong Police stopped the protest from approachingthe conference center. Teargas and rubber-bullets were used. Some of the protesters were injured. 900 people are besieged in Wanchai near the conference center. 3:30am: Arrests have now begun. Protesters are being loaded
(iv) Police have cornered and threatened to arrest 1000 protesters during a peaceful street occupation 1 block from the convention centre. They've been held there for the last 3 hours. Protesters are asking for support from the activist community to proceed with an international appeal to have the protesters released immideately, have their human rights respected, as the actions of the police are undignified.
From NOTOWTO blog:
1:30 AM HK time (12:30 PM NY time)
WTO protesters (too-jeng-dan) seem to be at the foot of the WTO convention center and they are completely surrounded by riot police. There are around 900-1000 with no one allowed in or out. The police are planning to arrest everyone inside the perimeter. The too-jeng-dan have not had food since lunch previous day. They cannot even use the bathroom. But their spirits are as high as can be with non-stop chanting and singing and banging on drums.
Earlier in the day rubber bullets were reported to have been fired and some were hospitalized.
The police are readying buses to transport the 1000 or so too-jeng-dan. They are also preparing tear gas squads for the charge in.
3:00 AM HK time (2:00PM NY time)
Got a call from e. She states calmly that they will all be arrested, but tells me not to worry because there are many of them. They have the power in numbers. The HK police cannot do anything to them!
3:30 AM HK time (2:30PM NY time)
Spoke with E again.
Police are all very young kids, inexperienced. Mostly they seem very frightened.
E was able to translate between the chief of police and the too-jeng-dan. It's strange but the chief of police seems very sympathetic to the farmers’ cause and understands why they are protesting but still explains that he must restore order.
The HK police have no precedent for such violent and mass arrests so they are very procedural and everything is taking a lot of time.
The protesters have agreed to be arrested, but one by one. There are tons of reporters and cameras covering this whole event. The WTO too-jeng-dan have already made their voices heard and will not struggle when taken.
They are being taken one by one and the HK police have promised to be very gentle with them. Largely the HK police are very young, frightened and civil at the same time and it’s chief has so far been cooperative. (who knows how this will really play out though).
The WTO too-jeng-dan has so far been pepper sprayed, tear gassed, beat on with batons, electric batonned, water cannoned (they also mixed in pepper gas formula in the water to burn eyes & skin when sprayed), exposed to chilly HK winter winds, hunger and fatigue…so show a little bit of wear but they are still in strong fighting spirits.
D who went out earlier to the hospital to translate for an injured protester was arrested by the police. Same thing also happened to J when she went to the hospital. Otherwise the rest of the KEEPers are all together inside the perimeter. KEEPers are hungry and tired but are very inspired to be part of this historical struggle. They will never forget this experience.
That’s it for now. If there's more I will let you know.