KYIV, Ukraine (AP) — Russia pounded Kyiv with an hourslong barrage of missiles and drones today, killing at least 12 people in its deadliest assault on the Ukrainian capital since July and drawing a rare rebuke of Moscow from U.S. President Donald Trump just as peace efforts were coming to a head.

The attack kept residents on edge for about 11 hours, with many staying awake all night while loud explosions reverberated around the city and flashes of light punctuated the sky. Families gathered in public air-raid shelters, some of them bringing cats and dogs. The strikes that began around 1 a.m. hit at least five neighborhoods and heavily damaged multiple residential buildings. Around 90 people were wounded.

Ukrainian President Volodymyr Zelenskyy said he would cut short his official trip to South Africa and return home as the city reeled from the bombardment. It appeared to be Russia’s biggest attack on Kyiv in nine months, and Zelenskyy called it one of Russia’s “most outrageous.”

Trump, who has long been reluctant to criticize the Kremlin, said he was “not happy” with it. He implored Russian President Vladimir Putin, to cease the devastating strikes.

“Not necessary, and very bad timing. Vladimir, STOP!” Trump wrote on his social media platform Truth Social.

Senior U.S. officials have warned that the Trump administration could soon give up its efforts to stop the war if the two sides do not come to agreement to halt the fighting.

The Ukrainian air force said Russia fired 66 ballistic and cruise missiles, four plane-launched air-to-surface missiles, and 145 Shahed and decoy drones at Kyiv and four other regions of Ukraine. Rescue workers with flashlights scoured the charred rubble of partly collapsed homes as the blue lights of emergency vehicles lit up the dark city streets.

The attack came as weeks of peace negotiations appeared to be culminating without an agreement in sight and hours after Trump lashed out at Zelenskyy, accusing him of prolonging the “killing field” by refusing to surrender the Russia-occupied Crimea Peninsula as part of a possible deal.

Kyiv Mayor Vitalii Klitschko announced that Friday would be an official day of mourning in the capital.

ZELENSKYY SAYS FUTURE OF NEGOTIATIONS DEPENDS ON MOSCOW

Zelenskyy has repeated many times during the more than three-year war that recognizing occupied territory as Russian is a red line for his country. He noted today that Ukraine agreed to a U.S. ceasefire proposal 44 days ago, as a first step to a negotiated peace, but that Russia’s attacks continued.

He said in South Africa that the latest attack meant the future of negotiations “depends on Russia’s intention because it is in Moscow where they have to make a decision.”

During recent talks, Russia has hit the city of Sumy, killing more than 30 civilians gathered to celebrate Palm Sunday, battered Odesa with drones and blasted Zaporizhzhia with powerful glide bombs.

The European Union’s foreign policy chief, Kaja Kallas, said the latest attack underscored that the main obstacle to ending the war is Russia.

“While claiming to seek peace, Russia launched a deadly airstrike on Kyiv,” she wrote on social media. “This isn’t a pursuit of peace, it’s a mockery of it.”

French President Emmanuel Macron said Putin should “stop lying” when he claims to want peace while continuing to bomb Ukraine.

Ukrainian Foreign Minister Andrii Sybiha said the attack showed that Putin is determined to press his bigger army’s advantage on the roughly 620-mile front line, where it currently holds the momentum.

“Putin demonstrates through his actions, not words, that he does not respect any peace efforts and only wants to continue the war,” Sybiha said on X. “Weakness and concessions will not stop his terror and aggression. Only strength and pressure will.”

Ukrainian Prime Minister Denys Shmyhal noted that since Russia’s February 2022 full-scale invasion of its neighbor, Russian attacks have killed some 13,000 civilians, including 618 children.

KYIV RESIDENTS SPENT THE NIGHT IN SHELTERS

At least 42 people were hospitalized following the attack on residential suburbs of Kyiv, Ukraine’s State Emergency Service said.

The dead included a brother and sister, age 21 and 19, according to Zelenskyy.

At a Kyiv residential building that was almost entirely destroyed, emergency workers removed rubble with their hands, rescuing a trapped woman who emerged from the wreckage covered in white dust and moaning in pain.

An elderly woman sat against a brick wall, her face smeared with blood and her eyes fixed on the ground in shock as medics tended to her wounds.

Fires were reported in several residential buildings, said Tymur Tkachenko, the head of the city military administration.

Oksana Bilozir, a student, suffered a head injury in the attack. With blood seeping from her bandaged head, she said that she heard a loud explosion after the air alarm blared and began to grab her things to flee to a shelter when another blast caused her home’s walls to crumble and the lights to go off.

“I honestly don’t even know how this will all end, it’s very scary,” said Bilozir, referring to the war. “I only believe that if we can stop them on the battlefield, then that’s it. No diplomacy works here.”

ZELENSKYY RETURNING FROM SOUTH AFRICA

Zelenskyy said in a Telegram post that he would fly back to Kyiv after meeting with South African President Cyril Ramaphosa.

The Ukrainian leader had hoped to recruit further South African support in efforts to end his country’s war with Russia, now in its fourth year.

The U.N. Office for the Coordination of Humanitarian Affairs said the Kyiv attack was “yet another appalling violation of international humanitarian law.”

“Civilians must never be targets. This senseless use of force must stop,” it said in a statement.

Anastasiia Zhuravlova, 33, a mother of two, was sheltering in a basement after multiple blasts damaged her home. Her family was sleeping when the first explosion shattered their windows and sent kitchen appliances flying in the air. Shards of glass rained down on them as they rushed to take cover in the corridor.

“After that, we came to the shelter because it was scary and dangerous at home,” she said.

In Kyiv’s Sviatoshynskyi district, the attack flattened a two-story residential building and heavily damaged nearby multistory buildings. Rescue work continued through the morning.

At a nearby school-turned-relief center, children helped parents cover blown-out windows with plastic while others queued for government compensation. Many stood in blood-stained clothes, still shaken.

Associated Press journalist Michelle Gumede in Pretoria, South Africa, contributed to this report.