MULESHOE, Texas — A hacking group linked to Russia is suspected of performing a cyberattack that caused a water facility tank in North Texas to overflow in January, according to CNN.

U.S. cybersecurity firm Mandiant reported the news on Wednesday.

The incident happened in Muleshoe, northwest of Lubbock, when an outside entity hacked into the city’s water tank software, which allows operators to interact with and control the tank. The tank overflowed for 30 to 45 minutes before officials took the machine offline and regained control of the system.

According to CNN, Mandiant found that hackers linked to Russia claimed responsibility for the cyberattack in Muleshoe on social media platform Telegram.

It was unclear whether Russia’s GRU military intelligence agency was responsible for the attack. But, if GRU or one of its representatives is confirmed to be involved, it would show an increase in a Russian group targeting critical infrastructure in the U.S. The group is known for focusing on Ukraine.

The FBI has been investigating the incident.

Two nearby Texas cities, also in North Texas, reported cybersecurity concerns after similar incidents. In Lockney, officials found “suspicious activity” in their city's SCADA system, a program that helps with the oversight of water plants.

In nearby Hale Center, hackers unsuccessfully tried to break into the city's firewall. In response, the town disabled access to its own SCADA system.

City managers from Lockney and Hale Center did not identify the hackers. Buster Poling, Lockney’s city manager, said town officials were able to catch the attempt early, so there was ultimately no impact on the city’s system.