Relatives of injured or missing workers stand in front of Mexican Marines blocking the access to Mexican national oil company Pemex's Pajaritos petrochemical complex in Coatzacoalcos, Veracruz state, Mexico, April 21, 2016. (Photo by Angel Hernandez/Reuters)





A soldier stands guard atop a vehicle while blocking the access to Mexican national oil company Pemex's Pajaritos petrochemical complex in Coatzacoalcos, Veracruz state, Mexico, April 21, 2016. (Photo by Angel Hernandez/Reuters)





Relatives of injured or missing workers scuffle with Mexican marines blocking the access to Mexican national oil company Pemex's Pajaritos petrochemical complex in Coatzacoalcos, Veracruz state, Mexico, April 21, 2016. (Photo by Angel Hernandez/Reuters)





Soldiers wearing surgical masks patrol the perimeter of Mexican national oil company Pemex's Pajaritos petrochemical complex in Coatzacoalcos, Veracruz state, Mexico, April 21, 2016. (Photo by Angel Hernandez/Reuters)





Relatives of injured or missing workers scuffle with Mexican marines blocking the access to Mexican national oil company Pemex's Pajaritos petrochemical complex in Coatzacoalcos, Veracruz state, Mexico, April 21, 2016. (Photo by Angel Hernandez/Reuters)





Student protesters hit a riot police vehicle during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





Student protesters clash with riot policemen during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





Student protesters run away as a riot police vehicle releases a jet of water during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





A student protester throws a stone against a riot police vehicle during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





A student protester runs away from riot policemen during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





A student protester gestures in front of riot police vehicles during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





Student protesters attend a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





A student protester throws a stone against a riot police vehicle during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Ivan Alvarado/Reuters)





Student protesters run away as a riot police vehicle releases a jet of water during a demonstration to demand changes in the education system in Valparaiso, Chile, April 21, 2016. (Photo by Rodrigo Garrido/Reuters)





A student painted as a clown performs next to a police officer during a demonstration to demand changes in the education system in Valparaiso, Chile, April 21, 2016. (Photo by Rodrigo Garrido/Reuters)





A riot policeman jumps over a molotov bomb during clashes with student protesters during a demonstration to demand changes in the education system in Santiago, Chile, April 21, 2016. (Photo by Clemente Villavicencio/Reuters)





A protester throws balloons with color paint during a protest against the government, in front a government building in Skopje, Macedonia, April 21, 2016. (Photo by Ognen Teofilovski/Reuters)





Demonstrators clash with police during a protest against the government, in front of the EU office in Skopje, Macedonia April 21, 2016. (Photo by Ognen Teofilovski/Reuters)





A protester throws balloons with color paint during a protest against the government, in front of a government building in Skopje, Macedonia April 21, 2016. (Photo by Ognen Teofilovski/Reuters)





Protesters spill buckets of color paint during a protest against the government, in front of a government building in Skopje, Macedonia April 21, 2016. (Photo by Ognen Teofilovski/Reuters)





A demonstrator draws a heart shape on a police shield during a protest against the government, in front of the EU office in Skopje, Macedonia April 21, 2016. (Photo by Ognen Teofilovski/Reuters)