42nd Separate Internal Troops Brigade
Identity
This record matches the historical HQ site of military unit 6531 at 56 Barrikad Street, Irkutsk. Archived procurement material and registry data place v/ch 6531 there, and the same address is now listed by the Rosgvardiya Directorate for Irkutsk Oblast. SPARK also shows the legal entity for v/ch 6531 was liquidated on 27 April 2018, so the brigade name appears to be a legacy designation rather than a clearly current legal title. ([tenderguru.ru](https://www.tenderguru.ru/tender/8918302?utm_source=openai))
Angarsk elements
The two Angarsk placemarks are consistent with corroborated subordinate garrisons. A fire-safety declaration registered on 30 January 2026 places the headquarters building of v/ch 3695 at Angarsk, New-4 microdistrict, Building 100. SPARK lists v/ch 3466 at Angarsk, Quarter 220, Structure 1, under the Federal Service of National Guard Troops. ([digital.mchs.gov.ru](https://digital.mchs.gov.ru/fgpn/declaration/38-08-2026-000951/pdf))
Mission split
Available sources show mixed public-order and facility-security roles across the Irkutsk-Angarsk cluster. Kommersant reported in September 2005 that a special motorized subunit based on v/ch 6531 began street-patrol duties in Irkutsk. Irkutsk regional government documents identify officers from v/ch 3695's battalions of "operational designation," and OGIRK in September 2022 described the unit as the Angarsk operational-purpose regiment. For v/ch 3466, procurement summaries show contracting with the Angarsk Electrolysis Chemical Combine (AЭХК), and local coverage describes the unit as guarding AЭХК output and escorting it across Russia; that escort detail is supported mainly by local reporting and should be treated as credible but not fully independently verified. ([kommersant.ru](https://www.kommersant.ru/doc/605779?utm_source=openai))
Critical infrastructure relevance
AЭХК is a Rosatom fuel-cycle site in Angarsk. TASS reported in December 2023 that the enterprise was resuming uranium-hexafluoride enrichment, and in December 2025 reported planned centrifuge modernization there as part of Russia's uranium-enrichment complex. Taken together with the 3466-AЭХК links above, the Angarsk garrison appears tied to protection of high-value nuclear fuel-cycle infrastructure and related movements, although the precise guard perimeter and convoy responsibilities are not publicly detailed. ([tass.ru](https://tass.ru/ekonomika/19460651?utm_source=openai))
Continuity
The "42nd Separate Internal Troops Brigade" label is historically attested in regional reporting, including OGIRK's December 2008 reference to v/ch 3695 as part of the 42nd Internal Troops Brigade. But the legal entity for v/ch 6531 was later liquidated, while v/ch 3695 and v/ch 3466 remain publicly traceable in 2026-era records, and 3466 received a battle banner in Angarsk in 2024. The safest analytic reading is a legacy brigade HQ in Irkutsk with surviving or successor Rosgvardiya garrisons in Angarsk, not a publicly confirmed current brigade headquarters under the same old title. ([ogirk.ru](https://www.ogirk.ru/2008/12/12/5395/?utm_source=openai))