Evidently you are talking about this clash: http://www.mizzima.com/news/inside-burm ... ktila.html
Numerous monks participated as well in various protests, e.g. Letpadaung copper mine protest .
I searched for a first-person explanation from a monk, and came up with:
"Several years ago, I interviewed Ashin Sopaka when he was in Thailand, having left Myanmar in 2003. The premise for his political activism, he said, lies in Buddhist doctrine that explicitly calls for the alleviation of human suffering: "If the people are suffering, then we have a responsibility - of course it [the suffering] is because of the political situation… [and] the political situation is connected to everything." While the government then attempted to slander protesting monks as heretics, many among the clergy consider activism as a natural obligation borne of Buddhist doctrine.
This was manifested in 2007 when monks organised to boycott religious duties for the generals, symbolised by the thousands who marched with their alms' bowls upturned. The act deeply unsettled the country's rulers, who are known for their almost paranoiac devotion to higher powers - the refusal to grant them and their colleagues merit, a cornerstone of Buddhist practice, had a tangible effect, with numbers of government workers who were effectively excommunicated during the uprising choosing to resign rather than continue to carry the stigma of being associated with the junta at that time."http://www.aljazeera.com/indepth/opinio ... 63504.html
Seems that since 2007 some part of the monks is intent to be politically and socially active, much like the "Bodu Bala Sena", or Buddhist Force, and The National Heritage Party (Jathika Hela Urumaya) in Sri Lanka, with all the consequences that ensue.