Republic, southwestern Russia. Part of the Chechen-Ingush autonomous republic of the former U.S.S.R., it became a republic within Russia in 1992, as did Ingushetia. It is populated mainly by Chechens, a Muslim ethnolinguistic group. Chechnya's demand for independence from Russia in 1992 led to an invasion by Russian troops in 1994. Fighting led to severe devastation of the area, and a series of cease-fires were negotiated and violated. A provisional peace treaty was signed in May 1997. Russian troops withdrew but returned in 1999, and heavy fighting resumed. In 2003 a new constitution was approved that devolved greater powers to the Chechen government but kept the republic in the Russian Federation. In 2009 Russia announced the end of its counterinsurgency operations in Chechnya. The capital, Grozny, is an oil centre with pipelines to the Caspian and Black seas.