The 2010 Mardakert clashes were a series of violations of the First Nagorno-Karabakh War ceasefire. They took place across the line of contact dividing Azerbaijan and the ethnic Armenian military forces of the unrecognized but de facto independent Nagorno-Karabakh Republic. Both sides accused the other of violating the ceasefire regime. These were the worst violations of the cease fire (which has been in place since 1994) in two years and left Armenian forces with the heaviest casualties since the Mardakert clashes of March 2008.