[1] Following the Khasavyurt Accord that ended the first conflict, Gakayev served as deputy commander of the Jundullah Islamic Brigade within the structure of the Eastern Front of the Chechen Republic of Ichkeria's (ChRi) armed forces, and he was also named Emir of the local Elistanzhi Jamaat of the Vedeno sector.

"[1] Gakayev was also reportedly a part of the 2004 Nazran raid commanded by Basayev, an assault which killed over sixty people and resulted in the capture of virtually the entire weapons cache of Ingushetia's police force.

The operation is considered a milestone in Gakayev's career and helped propel him from the ranks of everyday militants into the upper tier of rebel leadership.

[9] From 7 March to 7 October 2007, Gakayev served as the Minister of Internal Affairs in the last cabinet of the Chechen Republic of Ichkeria under the chairmanship of Dokka Umarov.

[4] On 25 July 2010, he has been briefly appointed by Umarov as Wali (governor) of the Vilayat Nokhchicho (in practice, the post of commander of the Chechen rebel forces).

[16] According to a press release from the Chechen Interior Ministry, on or around 17 January 2013 a well-camouflaged guerrilla base was discovered in a gorge in the Shatoi district.

[17] Over the next six days a search operation was carried out in the area; on 23 January a group of gunmen opened fire on police near Elistanzhi – Gakayev's native village – killing two and injuring six.

[17] Killed alongside Khuseyn and Muslim Gakayev were Isa Vagapov, Akhmed Labazanov, Umar Dadayev, Sidik Abazov, Ruslan Suleymanov, Aburayk Yusupkhadzhiyev, Ibrahim Saydhasanov, Vakha-Murad Bakayev, and Abuezid Dzhabrailov.