KYIV, Ukraine >> Russian airstrikes inflicted more damage on Ukraine on Thursday, with the latest barrage smashing into energy infrastructure, apartment buildings and an industrial site.

At least four people were killed and more than a dozen others wounded in drone and missile strikes around the country, authorities said.

Separately, U.N. Secretary-General António Guterres announced an extension of a four-month-old deal to ensure the safe delivery of export of grain, foodstuffs and fertilizers from Ukraine through the Black Sea just days before it was set to expire.

Guterres said in a statement the United Nations is also “fully committed” to removing obstacles that have impeded the export of food and fertilizer from Russia, which is one of two agreements struck between the two countries and Turkey in July. The deals signed in Istanbul are aimed to help bring down prices of food and fertilizer and avoid a global food crisis.

There was no immediate confirmation of the agreement from Russia.

Air raid sirens sounded all across Ukraine early Thursday amid fears that Moscow was unleashing its latest large-scale missile attack as the war approaches its nine-month milestone.

In Kyiv, the city’s military administration said air defenses shot down at least two cruise missiles and five Iranian-made exploding drones.

With the Kremlin’s forces on the ground being pushed back, Russia has increasingly resorted in recent weeks to aerial onslaughts aimed at energy infrastructure and other civilian targets in parts of Ukraine it doesn’t hold.

Ukrainian air defenses this week appear to have had far higher rates of successful shoot-downs than during previous barrages last month, analysts say. The improvement results in part from Western-supplied air defense systems.

But some missiles and drones still get through.

The Russian strikes hit Dnipro and Ukraine’s southern Odesa region for the first time in weeks. Valentyn Reznichenko, governor of the eastern Dnipropetrovsk region, said a large fire erupted in Dnipro after the strikes on the city hit an industrial target.

The attack wounded at least 14 people, among them a teenage girl, and all were being treated in city hospitals, Reznichenko said.

Ukraine President Volodymyr Zelenskyy posted on Telegram a video that he said was one of the blasts in Dnipro. The video from a vehicle dashcam shows a fiery blast engulfing a rainy road.

“This is another confirmation from Dnipro of how terrorists want peace,” Zelenskyy wrote, referring to the Kremlin’s forces. “The peaceful city and people’s wish to live their accustomed lives. Going to work, to their affairs. A rocket attack!”

Elsewhere, a Russian strike that hit a residential building killed at least four people overnight in Vilnia in the Zaporizhzhia region. Rescuers were combing the rubble for any other victims, according to Kyrylo Tymoshenko, a senior official in the Ukrainian presidential office.

Critical infrastructure was also hit in the northeast Kharkiv region, in the area of Izyum, wounding three workers, the regional administration said.

Dnipro mayor Borys Filatov said in a Facebook post that one of his staff was among the wounded and showed a photo of what he said was her coat pierced by a piece of shrapnel.

An infrastructure target was hit on the Odesa region, Gov. Maksym Marchenko said on Telegram, warning about the threat of a “massive missile barrage on the entire territory of Ukraine.”

Officials in the Poltava, Kharkiv, Khmelnytskyi and Rivne regions urged residents to stay in bomb shelters.

Thursday’s blasts followed the huge barrage of Russian strikes on Tuesday. That was the biggest attack to date on Ukraine’s energy infrastructure that also resulted in a missile hitting Poland.

Russia has increasingly targeted Ukraine’s power grid as winter approaches. The most recent barrage followed days of euphoria in Ukraine sparked by one of its biggest military successes — the retaking last week of the southern city of Kherson.

The head of Ukraine’s presidential office, Andriy Yermak, called the strikes on energy targets “naive tactics of cowardly losers” in a Telegram post on Thursday.

“Ukraine has already withstood extremely difficult strikes by the enemy, which did not lead to results the Russian cowards hoped for,” Yermak wrote, urging Ukrainians not to ignore air raid sirens.

Meanwhile, Ukrainian President Volodymyr Zelenskyy called the extension of the grain deal a “key decision in the global fight against the food crisis.”