A shootout between two of Ukraine’s top intelligence agencies has wounded at least three security officials, highlighting internal divisions within Kyiv’s security establishment.

On Wednesday morning, a gunfight broke out between Ukraine’s Main Directorate of Intelligence (HUR), a military arm which handles foreign intelligence, and the State Security Service (SBU), which focuses on domestic intelligence and counterterrorism activities.

Ukraine’s President Volodymyr Zelenskyy called the incident “an absolutely disgraceful situation”.

What’s behind the feud between SBU and HUR, and how significant is it?

What happened?

According to Ukrainian media reports, the incident between Kyiv’s top intel agencies took place in the capital’s Dniprovskyi district after the SBU took Stepan Kaplunov, deputy commander of the Russian Volunteer Corps (RVC) that fights for Ukraine, into custody. RVC is a subordinate of HUR.

Ukraine’s Prosecutor General’s Office said in a statement that SBU officers had received orders to prevent a “terrorist act” from Russia’s Federal Security Service (FSB).

“During a search at one of the addresses, a group of individuals carried out an armed attack on the SBU operational-investigative group,” the statement added.

“They tried to prevent the conduct of investigative actions and blocked the passage of law enforcement officers with cars,” the statement noted, adding that the attackers belonged to “one of the units of the Defense Forces of Ukraine.” According to local media reports, the attackers were part of HUR.

Ukraine’s Presidential Adviser Dmytro Lytvyn also confirmed the involvement of SBU and HUR in the shootout.

But the commander of HUR’s special unit “Timur,” in an interview with Radio Liberty/Radio Free Europe, accused the SBU of kidnapping Kaplunov “in broad daylight”.

The commander added that the SBU was the one which opened fire on HUR officers at the scene.

Taras Borovskyi, a lawyer representing Kaplunov, told Ukrainska Pravda that one HUR officer was shot in the leg, bleeding and in hospital. The second officer, he said, is also in a serious condition in the hospital, while the third officer is only slightly injured.

Who is Stepan Kaplunov?

Kaplunov is a Russian native who moved to Ukraine after Moscow annexed Crimea in 2014, according to Ukrainian media reports.

After serving in the Ukrainian armed forces, he joined the RVC in 2022 and has since been defending Ukraine in its war with Russia.

While Kaplunov is still a Russian citizen, Moscow added him to its list of “terrorists and extremists” because of his support for Ukraine.

Kaplunov told Radio NV on Thursday that he was abducted and interrogated over suspicions that he might be in touch with Russia’s FSB Security Service, according to The New Voice of Ukraine site.

How have Zelenskyy and his government responded?

In a statement on Telegram, Ukraine’s president said he had spoken to the country’s Prosecutor General Ruslan Kravchenko, who is investigating the incident with the State Bureau of Investigation.

“There must be accountability – including personnel decisions by the heads of the security services regarding the individuals involved – and internal investigations must be conducted within both agencies,” he said in the statement.

“Here in Ukraine, the only time shots may be fired is at Russian occupiers in defence of the country. Our state will never tolerate any other kind of shootout as something permissible,” he added.

Zelenskyy has since dismissed Oleg Khramov, the head of the SBU’s Department for the Protection of State Secrets.

Kyrylo Budanov, the head of Ukraine’s Presidential Office and a former HUR member, called for a “thorough and impartial investigation,” according to the RBC-Ukraine news agency.

“It is important to ensure a thorough and impartial investigation, but no one has the right to kidnap servicemen with impunity, open fire on the streets of our cities, give and carry out criminal orders,” he said.

How significant is the recent security shakeup?

The incident comes as Ukraine shakes up its security establishment amid the escalating war with Russia.

In January this year, Zelenskyy removed Vasyl Maliuk as the head of SBU, shifting him to focus directly on warfare missions against Russia.

Zelenskyy also named military intelligence chief Kyrylo Budanov as his new chief of staff and announced that Foreign Intelligence Service chief Oleh Ivashchenko will replace Budanov as head of the HUR.

“Ukraine needs greater focus on security issues, the development of the Defence and Security Forces of Ukraine, as well as on the diplomatic track of negotiations, and the Office of the President will primarily serve the ‌fulfilment of these tasks of our state,” Zelenskyy had said.

In July, Zelenskyy also fired Oleksandr Syrskii as the country’s commander-in-chief, appointing Mykhailo Drapatyi to lead the military.

The move came after six days of protests in the capital, Kyiv, caused by the removal of Defence Minister Mykhailo Fedorov, who had previously clashed with Syrskii.

According to a report by Carnegie Politika, the media and analysis platform of the Carnegie Russia Eurasia Center in Berlin, Zelenskyy’s security reshuffle “suggests a deliberate effort to tighten political coordination across the institutions that control coercive power”.

“The replacements come after anti-corruption investigations once again began reaching senior figures around the president, reviving tensions between the presidential administration and independent anti-corruption institutions,” the report noted.

“Whether this will translate into renewed pressure on the National Anti-Corruption Bureau of Ukraine remains to be seen, but the personnel changes clearly strengthen the presidential administration’s ability to shape the relationship between the security services and Ukraine’s law-enforcement architecture,” the report added.

Zelenskyy’s allies have also been accused of corruption.

Last November, a corruption scandal involving Zelenskyy’s business partner, political allies and a cast of presumed wrongdoers who profited from a nuclear power monopoly roiled Ukraine.

The agencies, Ukraine’s National Anti-Corruption Bureau (NABU) and the Specialised Anti-Corruption Prosecutor’s Office (SAPO), released video and audio recordings in which the group appears to use nicknames and codewords to discuss bribes and kickbacks amounting to tens of millions of dollars.

Zelenskyy, whose anticorruption presidential campaign resonated with voters in 2019, tried to curb the autonomy of both agencies in July after they opened investigations into his allies and former business partners. But he backed down after massive popular protests.