Russia said its security forces are continuing what it described as an “anti-terrorist” operation for a second day after attackers crossed the border from Ukraine.

“We are working to wrap up the anti-terrorist operation, security forces are doing all they can,” Belgorod Governor Vyacheslav Gladkov said Tuesday on his Telegram channel. It wasn’t yet safe for residents to return to their homes after they were evacuated from the area, he said, adding that two residents had been wounded in the fighting that erupted Monday.

The attack in the Belgorod region that borders Ukraine was carried out by Russian volunteer militias, Andriy Yusov, Ukrainian military intelligence spokesman, told Ukraine’s Suspilne broadcaster in an interview Monday. The “Freedom of Russia Legion” and the “Russian Volunteer Corps” were attempting to create a “security strip” to protect Ukrainian civilians, he said.

President Vladimir Putin was informed about the incursion in reports from the Defense Ministry and security officials, Kremlin spokesman Dmitry Peskov told Russian media. There were sufficient defense forces in the region to repel and destroy the attackers, he said.

It’s the second cross-border attack in Russia in two months, after Russian officials accused Ukraine in March of a sabotage attack on a village in the Byransk region that killed two civilians and wounded a 10-year-old boy. Kyiv denied the claim, calling it an attempt by Russia to boost public support for Putin’s invasion of Ukraine.

The attackers had armored vehicles and advanced 8 kilometers (5 miles) into Russian territory before being pushed back toward the border, according to one pro-Russian military blogger Rybar, whose Telegram channel has nearly 1.1 million subscribers.