He switched sides together with his brothers, Ruslan and Sulim in 1999 during the outbreak of the Second Chechen War and then became the commander of the Russian special forces unit Vostok.

During the First Chechen War the five Yamadayev brothers fought against the Russian troops and enjoyed great influence as field commanders.

[1] When the second war in Chechnya broke out in 1999, the Yamadayevs (including Dzhabrail, Sulim and Ruslan) voluntarily defected to Moscow's side.

On 5 March 2003, Dzhabrail Yamadayev was killed along with three of his bodyguards in his own house in the village of Dyshne-Vedeno by a bomb planted under a couch that he slept on after returning from a two-day operation in the mountains.

[2] In May 2008, remains belonging to Vakharsolt Zakayev, a former Vostok officer (platoon leader) who had disappeared about six months after that incident and was assumed to have been executed by his colleagues on suspicion in taking part in assassination, were found in the outskirts of Gudermes.