KYIV, Ukraine (AP) — A nighttime Russian ballistic missile attack targeted Kyiv early Wednesday, injuring at least 53 people including eight children, officials said, as the Ukrainian president went to Scandinavia in pursuit of further international military support for his country after a trip to Washington secured no new pledges.

A series of loud explosions could be heard in Kyiv at 3 am as the city’s air defenses were activated for the second time this week. Ukraine’s air force said Russia launched 10 ballistic missiles toward the capital and all were intercepted by air defenses.

The attack on the capital underscored the continuing threat to Ukraine from the Kremlin’s missile arsenal in the 21-month war. Russia has in recent months been stockpiling its air-launched cruise missiles from its heavy bomber fleet, according to a recent assessment by the UK Ministry of Defense.

That may herald another heavy winter bombardment of Ukraine’s power grid. Moscow last year targeted energy infrastructure in an effort to deny Ukrainians heat, light, and running water and break their fighting spirit.

As winter sets in and hinders troop movements, allowing little change along the front line, long-range air bombardment plays a growing role in the war.

Ukraine has dwindling supplies of air defense munitions and other ammunition. That prompted Ukrainian President Volodymyr Zelenskyy to visit Washington on Tuesday to persuade lawmakers to approve President Joe Biden’s request for $61.4 billion for Ukraine. His trip accomplished no breakthrough.

Zelenskyy said on Telegram on Wednesday that he and Biden agreed to work on increasing the number of air defense systems in Ukraine. “The terrorist state has just demonstrated how crucial this decision is,” Zelenskyy said, referring to the overnight strikes.

Zelenskyy on Wednesday met in Oslo with Nordic leaders who feel keenly the potential threat from nearby Russia and are among Kyiv’s staunchest supporters.

“Russia is eager to exploit divisions,” the senior leaders from Denmark, Iceland, Norway, Finland, and Sweden said in a joint statement in English. “We must continue to stand united against Russia’s illegal and immoral war.”

They vowed “comprehensive assistance” for Ukraine. “Now is not the time to tire,” the Nordic leaders said, amid signs of war fatigue among Kyiv’s foreign supporters.

“We are in a critical phase where Europe must continue to show its support,” Danish Prime Minister Mette Frederiksen said in a statement.

Separately, Latvia and Ukraine announced an agreement on the production of drones, which have become a key aspect of the war. They said they will aim to “enhance Ukraine’s technological superiority” in drone use.

Debris from intercepted missiles fell in Kyiv’s eastern Dniprovskyi district, injuring dozens of people, Kyiv Mayor Vitali Kitschko said on Telegram. Twenty people, including two children, were hospitalised, and 33 people received medical treatment on the spot.

An apartment building, a private house and several cars caught fire, while the windows of a children’s hospital were shattered, Klitschko said. Falling rocket debris also damaged the water supply system in the district.

It wasn’t immediately clear what type of missile was used in the Kyiv attack.

“It is difficult to imagine the consequences of these attacks if we don’t have air protection,” Ukraine’s Minister of Economy, Yulia Svyrydenko, said on X, formerly Twitter. “Each attack emphasises the urgent need for more protection, as Russia shows no intention of stopping.”

In other parts of Ukraine, 10 Russian drones were shot down, most of them in the Odesa region, the Ukrainian air force said.

Wednesday’s attack came as Zelenskyy visited Washington, where he made an impassioned plea to Congress to approve additional aid to fight Russia’s invasion.

Andriy Yermak, Zelenskyy’s chief of staff who was traveling with the president, said the interception of the missiles fired at Kyiv showed how Western support is helping Ukraine resist the Russian aggression.

“The effectiveness of Western weaponry in the hands of Ukrainian soldiers is beyond doubt,” Yermak wrote on Telegram.