Ukrainian President Viktor Yanukovych returned to work on Monday after four days of illness. Demonstrators across Ukraine demand that he step down. --Thea Breite (16 photos total)

An anti-government protester stands in front of a roadblock in Kiev on February 3, 2104. Tens of thousands of protesters, buoyed by pledges of support from Europe and the United States, rallied in Ukraine on Sunday in a bid to wring new concessions from President Viktor Yanukovych. More than 50,000 people could be seen on Kiev's barricaded Independence Square,that has become the epicenter of a two-month protest movement. (Angelos Tzortini/AFP/Getty Images)