KYIV, Ukraine -- Russia took aim at Western military supplies for Ukraine's government with early Sunday airstrikes in Kyiv that it said destroyed tanks donated from abroad, a claim denied by a Ukrainian official. Russian President Vladimir Putin warned that any Western deliveries of long-range rocket systems to Ukraine would prompt Moscow to hit "objects that we haven't yet struck."
The cryptic threat of a military escalation from the Russian leader didn't specify what the new targets might be, but it comes days after the United States announced plans to deliver $700 million of security assistance for Ukraine. Those weapons include four precision-guided, medium-range rocket systems, helicopters, Javelin anti-tank weapon systems, radars, tactical vehicles and more.
Military analysts say Russia is hoping to overrun Ukraine's embattled eastern industrial Donbas region, where Russia-backed separatists have fought the Ukrainian government since 2014, before any U.S. weapons that might turn the tide arrive. The Pentagon said last week it will take at least three weeks to get the precision U.S. weapons onto the battlefield.
Ukraine's General Staff said Russian forces fired five X-22 cruise missiles from the Caspian Sea toward Kyiv, and one was destroyed by air defenses. Four others missiles hit "infrastructure facilities," but Ukraine said there were no casualties. Nuclear plant operator Energoatom said one cruise missile buzzed close to the Pivdennoukrainsk nuclear plant, 350 kilometers (220 miles) to the south, and warned of the catastrophic dangers if such a near miss turned into a direct hit.
In a posting on the Telegram app, the Russian Defense Ministry said high-precision, long-range air-launched missiles were used. It said the strikes on the outskirts of Kyiv destroyed T-72 tanks supplied by Eastern European countries and other armored vehicles located in buildings of a train car repair business.
But the head of Ukraine's railway system rejected the claim that tanks were inside. Oleksandr Kamyshin said four missiles hit the Darnytsia car repair plant, but no military equipment has been stored there. He said the site was used to repair gondolas and grain carriers for exporting products.
"Russia has once again lied," he wrote on Telegram. "Their (Russia's) real goal is the economy and the civilian population. They want to block our ability to export Ukrainian products."
In a television interview that aired Sunday, Putin lashed out at Western deliveries of weapons to Ukraine, saying they aim to prolong the conflict.
"All this fuss around additional deliveries of weapons, in my opinion, has only one goal: To drag out the armed conflict as much as possible," Putin said. He insisted such supplies were unlikely to change the military situation much for Ukraine's government, which he said was merely making up for losses of similar rockets that they already had.
If Kyiv gets longer-range rockets, he added, Moscow will "draw appropriate conclusions and use our means of destruction, which we have plenty of, in order to strike at those objects that we haven't yet struck."
The U.S. has stopped short of offering Ukraine longer-range weapons that could fire deep into Russia. The four medium-range High Mobility Artillery Rocket Systems included in the security package include launchers on wheels that allow troops to strike a target and then quickly move away -- which could be useful against Russian artillery on the battlefield.
The Spanish daily El Pais reported Sunday that Spain was planning to supply anti-aircraft missiles and up to 40 Leopard 2 A4 battle tanks to Ukraine. Spain's Ministry of Defense did not immediately respond to a request for comment.
A billowing pillar of smoke filled the air with an acrid odor in Kyiv's eastern Darnystki district over the charred, blackened wreckage of a warehouse-type structure. Soldiers blocked off a nearby road leading toward a large railway yard.
Before Sunday's early-morning attack, Kyiv hadn't faced any such Russian air strikes since the April 28 visit of U.N. Secretary-General António Guterres. The attack triggered air raid alarms and showed that Russia still had the capability and willingness to hit at Ukraine's heart, despite abandoning its wider offensive across Ukraine to focus its efforts to capture territory in the east.
Russia's invasion of Ukraine on Feb. 24 has led to untold tens of thousands of civilian and troop deaths, driven millions from their homes, sparked vast sanctions against Putin's government and allies, and strangled exports of critical wheat and other grains from Ukraine through Black Sea ports -- limiting access to bread in Africa, the Middle East and beyond.
Energoatom said one Russian cruise missile came dangerously close to the Pivdennoukrainsk nuclear power plant. It said the missile "flew critically low" and that Russian forces "still do not understand that even the smallest fragment of a missile that can hit a working power unit can cause a nuclear catastrophe and radiation leak."
In recent days, Russian forces have focused on capturing Ukraine's eastern cities of Severodonetsk and Lysychansk. On Sunday they continued their push, with missile and airstrikes on cities and villages of the Luhansk region of the Donbas.
The U.K. military said in its daily intelligence update that Ukrainian counterattacks in Severodonetsk were "likely blunting the operational momentum Russian forces previously gained through concentrating combat units and firepower." Russian forces previously had been making a string of advances in the city, but Ukrainian fighters have pushed back in recent days.
The statement also said Russia's military was partly relying on reserve forces of the separatists in the Luhansk region.
"These troops are poorly equipped and trained, and lack heavy equipment in comparison to regular Russian units," the intelligence update said, adding that "this approach likely indicates a desire to limit casualties suffered by regular Russian forces."
Far from the battlefield, Ukraine's national soccer players are hoping to secure a World Cup spot when the team takes on Wales later Sunday in Cardiff.
On the diplomatic front, Russian Foreign Minister Sergey Lavrov was heading to Serbia for talks with President Aleksandar Vucic early this week, followed by a visit to Turkey on Tuesday, where the Russian envoy is expected to discuss Ukraine with his Turkish counterpart.
Turkey has been trying to work with the U.N. and the warring countries to help clear the way for Ukrainian grain to be exported to Turkish ports, though no deal appeared imminent.
Ukrainian authorities said Ukraine and Russia had exchanged bodies of killed troops, in the first officially confirmed swap. Ukraine's Ministry for Reintegration of Occupied Territories said Saturday each side had exchanged 160 bodies two days earlier on the front line in the southern Zaporizhzhia region.
Russian officials haven't commented on the exchange.