LONDON and KHARKIV -- Several drones struck Moscow early on Tuesday, damaging residential buildings in the Russian capital, the mayor said.
The pre-dawn attack "caused minor damage to several buildings" in a residential area, according to Moscow Mayor Sergey Sobyanin. Some residents were evacuated from their apartments due to "safety reasons" as first responders surveyed the damage, Sobyanin said.
"All municipal emergency services are currently at the scene of the incident," the mayor wrote on his official Telegram channel. "They will find out the circumstances of what happened."
It's believed to be the first major drone strike on a residential area of Moscow.
No one was seriously injured in the attack, according to Sobyanin. Two people sought and received medical attention on site for unspecified injures but did not require hospitalization, the mayor said.
Russian emergency services told state news agency TASS that drone-like fragments were found around at least one of the buildings and that apartment windows were shattered on several floors.
Eight drones targeted Moscow, five of which were shot down while the other three were jammed, causing them to veer off course, according to the Russian Ministry of Defense.
The rare attack came as Russia continues to wage war in neighboring Ukraine. The Russian defense ministry called Tuesday's drone strike a "terrorist attack" by the "Kyiv regime" and said Moscow will react "as harshly as possible to the actions of Ukrainian militants."
Kremlin spokesman Dmitry Peskov said Tuesday's drone attack on Moscow was Kyiv's retaliation against the effective Russian strikes "on a decision-making center" on Sunday. Russian President Vladimir Putin later specified that the headquarters of Ukraine's military intelligence was among the targets hit.
"In response, the Kyiv regime chose the path of intimidation of Russian citizens and strikes on residential buildings," Putin said Tuesday. "This, of course, is a clear sign of terrorist activity."
He went on, "The Moscow air defense system has worked properly, satisfactorily, although there is work to be done. It is clear what needs to be done to seal the air defense of the capital, and we will do it."
Meanwhile, in recent days, Russia has launched a series of drone and missile attacks on Kyiv. At around 2 a.m. local time on Tuesday, Kyiv residents once again awoke to the sound of air raid sirens as dozens of Russian drones targeted the city for a third straight day.
Most of the drones were intercepted and shot down but the fallen debris sparked fires that engulfed several cars, houses and residential buildings, according to Kyiv Mayor Vitali Klitschko. At least one person was killed and 33 others were injured.
"If the Russians can make Kyiv a nightmare, why do the people of Moscow rest?" Klitschko said in a televised address on Tuesday.
Tuesday's attack on Kyiv marked Russia's 17th round of strikes on the Ukrainian capital this month, according to a spokesperson for the United States National Security Council.
"Russia started this unprovoked war against Ukraine," the spokesperson told ABC News on Tuesday. "Russia could end it at any time by withdrawing its forces from Ukraine instead of launching brutal attacks against Ukraine’s cities and people every day."
The recent escalation in drone and missile attacks on both sides comes ahead of a major Ukrainian counteroffensive, which Ukrainian officials say will happen "soon."
A senior Ukrainian commander told ABC News on Sunday that preparations for that counteroffensive were in full swing.
Col. Oleksandr Bakulin, who commands Ukraine’s 57th motorized infantry brigade, made up of around 6,000 men near the eastern Ukrainian city of Bakhmut, said the counteroffensive "will not begin with one single strike." The limited Ukrainian offensive actions near Bakhmut over the past two weeks were part of a bigger plan that will eventually lead to a more significant counteroffensive by Ukrainian forces, according to Bakulin.
He cautioned, however, that Russia could also attempt to go on the offensive in areas too.
"In some parts of the front line we are pushing, in other areas the enemy has more of the initiative," Bakulin said.
ABC News' Will Gretsky, Joe Simonetti, Tanya Stukalova and Karen Travers contributed to this report.