Armed thugs. Motorcycle gangs. Their defense of Chavismo - la revolución bolivariana - involved disrupting peaceful opposition rallies with threats of violence. They and other 'colectivos chavistas' are the reason the death toll of the current nationwide demonstrations against the government of Venezuela keeps climbing. The police, the National Guard look the other way when these armed, black-masked hooligans show up.
"Over a year has passed now, since an ABC journalist had the opportunity to talk with Alberto “Chino” Carías, chief of the Tupamaros, during Hugo Chávez’s last electoral campaign. When he was asked about the murder of three people during an opposition rally, his answer was “in every war, there is death.”" - from a blog by Marcela Estrada of Caracas, Venezuela.
Check out their website: http://www.tupamaro.org.ve/