Following the dissolution of the Soviet Union in 1991, Chechnya declared independence from the Russian Federation. The Russian officials refused their independence declaration, sparking tensions. This ultimately escalated into a full war when 25,000 Russian soldiers crossed into Chechnya on 11 December 1994. The war ended with Chechen "de facto" independence and Russian troop withdrawal in 1996. The second conflict escalated again in 1999, and its counterinsurgency waged until 2009. It concluded by Russia taking full control of Chechnya and instaling a pro-Russian government. Numerous war crimes were recorded, mostly by the Russian armed forces.