The latest Occupy Wall Street encampment to fall to a city police force was in Denver overnight, where retreating protesters left cops a set of burning shelters to deal with as they made their way out of the camp. The shelters were a key element of that encampment's wrangling with the city, which it sued for the right to remain in the downtown Civic Center. Denver's pretty cold in the winter, obviously, so occupiers can't survive without their shelters -- and as you can see in the photo, those shelters were more substantial than regular camping tents. Because of the cold, Occupy Denver also employed warming fires, so unlike other sites, there was plenty of combustion already when the cops arrived. The Denver Post described the scene as police moved in on the relatively small group of about 40 protesters who first "Tebowed" and then sang "God Bless America" before making their scorched-tent retreat:

The clash had been intense and swift, with police shoving protestors and journalists alike with their batons, but it appeared only one protestor was taken into custody.

Afterwards, White said officers had hoped to ask the protestors a final time to remove their belongings, but when two prostestors began setting the shelters aflame, officers and firefighters had to move it.

A firetruck moved in to douse the flames as a battery of police closed ranks shouting, "Move back!" to allow firefighters access.

Police said two protestors were arrested on arson charges and two were arrested on charges of failing to obey a lawful order.

The last time Denver police clashed with protesters, back in late October, the crowd was a lot bigger and the confrontation more violent. But the fiery retreat made the potential for serious danger far greater as cops moved in on protesters in the middle of the night.   No injuries have been reported yet, but the Post got some great photos.