Ukraine is working with the Federal Bureau of Investigation (FBI) and US companies to collect evidence of war crimes committed by Russians, including geolocation and cellphone information.

Ukrainian authorities have been gathering digital information from battlefields and war-torn Ukrainian cities since Russia invaded the country in February 2022, said Alex Kompanets, an FBI special agent who previously served as the agency’s legal attaché in Ukraine.

“Gathering that data, analyzing that data, working through that data is something that the FBI has experience in,” Kobzanets said at the RSA cybersecurity conference in San Francisco.

The work includes examining cell phone information, forensic analyzes of DNA samples, as well as analysis of body parts collected from battlefields, he said.

“The next step is to work with US national carriers, and transfer that information … securing subscriber information, geolocation information, where possible,” Kobzanets added.

The work reflects deepening cooperation between the US and Ukraine on the cyber front, where Russia is a common adversary for both countries.

Kobzanets added that the FBI has been working for the past year and a half to also help Ukraine identify Russian collaborators and spies operating in Ukraine and Russian forces operating out of Kiev while the invasion was underway.

Security firms and US officials are important partners for Ukraine in its efforts to fend off Russian cyberattacks, which it has faced since at least 2015.

Ilya Vityuk, head of the Cybersecurity Department at the Security Service of Ukraine, said that while the number of Russian attacks against Ukraine has increased in recent years, in recent months they have become more targeted.

“It’s very difficult to prove in a criminal case who is responsible,” Vityuk said. “It’s very important for us to get as much information as possible about Russian cybercriminals … because we’re gathering all that information and putting it into our criminal cases.”

“We do believe that this cybercrime case is something new,” he added. “It is here that we have seen the first full-scale cyber war.”