Protesters use a large slingshot to hurl a Molotov cocktail at police in central Kiev, Ukraine, Thursday Jan. 23, 2014. Thick black smoke from burning tires engulfed parts of downtown Kiev as an ultimatum issued by the opposition to the president to call early election or face street rage was set to expire with no sign of a compromise on Thursday. (AP Photo/Sergei Grits). Sergei Grits

Christopher Rivera

The body of boxer Christopher Rivera, who was shot to death, is propped up in a fake boxing ring during his wake at the community recreation center within the public housing project where he lived in San Juan, Puerto Rico. Ricardo Arduengo is a Puerto Rico-based photojournalist shooting for the Associated Press. See more of his work here.
Members of the Basij paramilitary militia listen to their trainer during exercises in Tehran, Iran. The Basij has its roots as volunteer fighters during the 1980-88 war with Iraq. It then developed as a grass-roots defender of the system; taking on roles such as Islamic morality police at checkpoints and parks or as shock troops busting up pro-reform gatherings or publications. Precise numbers on Basij membership are not published, but some estimates range as high as 1 million or more. Ebrahim Noroozi is a Tehran-based photographer. He has been working with Iran’s Fars New Agency since 2004. See more of his work here. AP Photo/Ebrahim Noroozi
A protestor shouts slogans during a demonstration in Madrid, Spain, supporting the on-going protest in Ukraine against Viktor Yanukovych’s government. Andres Kudacki is a stringer working for the Associated Press in Madrid. Check out more of his work here. AP Photo/Andres Kudacki
Nick warms himself on a steam grate with three other homeless men by the Federal Trade Commission, just blocks from the Capitol, during frigid temperatures in Washington, Saturday, Jan. 4, 2014. Jacquelyn Martin is an Associated Press staffer based in Washington DC. Check out more of her work here. AP Photo/Jacquelyn Martin
A protester throws a Molotov cocktail onto a fire during clashes with police in central Kiev, Ukraine, early Saturday, Jan. 25, 2014. As riots spread from Ukraine’s embattled capital to nearly half of the country, President Viktor Yanukovych promised to reshuffle his government and make other concessions – but a top opposition leader said nothing short of his resignation would do. Hours after the president’s comments, huge fireballs lit up the night sky in central Kiev and plumes of thick black smoke rose from burning tires at giant barricades erected by protesters. Sergei Grits is an Associated Press staff photographer based in Eastern Europe. His images from the on-going protests in Ukraine are some of the most dynamic we’ve seen. AP Photo/Sergei Grits
Orthodox priests pray as they stand between pro-European Union activists and police lines in central Kiev, Ukraine, early Friday, Jan. 24, 2014. A top Ukrainian opposition leader on Thursday urged protesters to maintain a shaky cease-fire with police after at least two demonstrators were killed in clashes. AP Photo/Sergei Grits
Egyptians hold national flags during a rally in Tahrir Square, in Cairo, Egypt, Saturday, Jan. 25, 2014. Egyptian riot police have fired tear gas to disperse hundreds of supporters of ousted Islamist President Mohammed Morsi protesting as the country marks the third anniversary of the 2011 uprising, as supporters of the military gathered in rival rallies in other parts of the capital. Khalil Hamra is an Associated Press photojournalist currently located in Egypt. See more of his work here. AP Photo/Khalil Hamra
Eric Frenzel of Germany, right, celebrates in front of Jason Lamy Chappuis of France, center, and Mario Stecher of Austria, left, in the finish area during the men Nordic combined team Gundersen 4×5 km competition at the Nordic Combined FIS World Cup in Oberstdorf, southern Germany. Germany won the competition. France placed second and Austria placed third. Jens Meyer is an Associated Press photographer based in Germany. AP Photo/Jens Meyer
African migrants sit on top of a Holocaust memorial installation in Rabin’s square, after marching in Tel Aviv, demanding work rights and better treatment from the Israeli government. Ariel Schalit is an AP staffer based in Isreal. See more work here. AP Photo/Ariel Schalit
A Palestinian worker collects charcoal in the West Bank village of Yabed, near Jenin city. Mohammed Ballas and Associated Press staff photographer based in Palestine. In 2006, he won a 3rd place World Press Photo award. You can check out that photo here (Warning: It is a bit graphic in nature). AP Photo/Mohammed Ballas
Lightning strikes Chile’s Cordón Caulle Volcano in a series of images that went viral earlier this month. We spoke with the photographer behind the series, Francisco Negroni, in an interview on our sister site, Check out more of Negroni’s work here. Francisco Negroni

Our Photojournalism of the Month gallery highlights moments of exceptionally strong documentary photography, culled from the daily output of wire photographers from around the world. Want more photojournalism? Check out The Best Photojournalism of 2013.