A botched detention operation turned into open interagency warfare, forcing Zelensky to sack officials from both services.
Intelligence Lead
A firefight between Ukraine's domestic security service (SBU) and its military intelligence directorate (HUR) erupted in Kyiv's Dniprovskyi district on 2 September, wounding at least three HUR personnel and exposing an unprecedented breakdown in coordination between the country's two principal intelligence organs. The clash originated in the SBU's nine-day secret detention of Stepan Kaplunov, deputy commander of the HUR-affiliated Russian Volunteer Corps, whom the SBU accuses of acting as an FSB asset tasked with assassinating a Russian opposition figure based in Kyiv. President Volodymyr Zelensky has ordered a criminal investigation and dismissed senior officials from both services, but the episode has reopened long-standing turf tensions between SBU and HUR at a moment when internal cohesion is operationally critical.
Situation Report
Residents of Kyiv's Bereznyaky area were woken before dawn on 2 September by sustained gunfire as two vehicles exchanged shots on a residential street. Ukrainian outlets reported that SBU officers fired on a HUR unit attempting what Kyiv media described as a rescue or extraction operation; footage circulating on social media showed bullet-scarred vehicles and blood at the scene. Three HUR service members were confirmed wounded. Police cordoned off the street, and Zelensky publicly called the incident "absolutely disgraceful," noting that "shooting is permitted only against occupiers."
The SBU has stated the confrontation grew out of a counter-espionage operation against Stepan Kaplunov, deputy commander of the Russian Volunteer Corps (RVC), a Russian-nationalist paramilitary unit that fights under HUR's command structure against Moscow. According to the SBU, Kaplunov had established contact with Russia's FSB and was tasked with assassinating a leader of the Russian opposition movement operating in Kyiv, with the attack allegedly timed for Ukraine's Independence Day. The SBU says it detained Kaplunov to disrupt the plot and obtained a signed confession.
Kaplunov has denied the allegations. In a 3 September social media statement, he said he was seized near his home on 23 August by men identifying themselves as police, then handcuffed, blindfolded, and held for nine days at what he described as a secret detention site, where he signed the confession only under sustained psychological pressure and threats. HUR has offered a competing account of the shootout's origin, and the two services have since traded further accusations and denials through Ukrainian and Russian-language media.
Zelensky has dismissed Oleh Khramov, head of the SBU's department for the protection of state secrets, and ordered the removal of a deputy head from each agency. Ukraine's Prosecutor General has opened a criminal case naming one SBU officer and one HUR officer over the shooting. The president's office has demanded a "thorough investigation" into both the detention and the firefight, and has not yet indicated a timeline for its conclusion.
Background & Context
SBU and HUR occupy distinct but frequently overlapping mandates: SBU handles domestic counterintelligence and counterterrorism, while HUR runs foreign and battlefield intelligence, including unconventional units such as the Russian Volunteer Corps, a formation of Russian nationalists and former far-right militants fighting alongside Ukraine's armed forces. RVC's ambiguous status, an irregular unit with a leadership drawn from actors Moscow considers extremists, has made it a recurring subject of counterintelligence scrutiny, and Kaplunov is not the first RVC figure to face SBU suspicion of Russian penetration.
Friction between SBU and HUR predates this incident. Both services have historically competed over recruitment of high-value assets, control of irregular formations operating inside occupied territory, and credit for high-profile operations against Russian targets. Wartime expansion of both agencies' operational footprints, often with minimal formal deconfliction protocols between them, has widened the space for exactly this kind of jurisdictional collision.
The episode also lands amid heightened scrutiny of Ukraine's security architecture more broadly, as Kyiv navigates parallel pressure from Washington over ceasefire terms and continued Russian missile and drone strikes on the capital. A public, video-documented gunfight between two state intelligence services is a propaganda opportunity Moscow's information apparatus is well-positioned to exploit.
Analysis & Assessment
The incident is assessed as primarily a symptom of unresolved institutional rivalry rather than direct Russian engineering, though the FSB-recruitment allegation against Kaplunov, if substantiated, would represent a genuine counterintelligence breach inside an irregular unit with battlefield access. The more immediate risk to Kyiv is reputational and operational: allied intelligence services weighing further liaison and information-sharing with Ukraine will read an unauthorized armed clash between SBU and HUR as evidence of command fragmentation at a sensitive point in the war.
Zelensky's rapid personnel moves, dismissing officials from both sides rather than favoring one service, suggest an attempt to contain the episode as an isolated failure of protocol rather than validate either agency's narrative. This is likely to leave the underlying jurisdictional ambiguity between SBU and HUR over irregular units unresolved, and further incidents involving RVC-linked or similarly ambiguous formations should be considered plausible absent a formal deconfliction mechanism.
Kaplunov's public allegation of coerced confession under secret detention, if corroborated, would additionally expose SBU to scrutiny over detention practices independent of the underlying espionage question, a second line of reputational risk running in parallel with the interagency dispute.