A Russian airstrike hit a Ukrainian military base a few miles from the border with NATO member Poland, killing 35 people and injuring dozens more as Moscow steps up its offensive across Ukraine, triggering angry demonstrations across Europe.

A local official said 35 people were killed and 134 wounded in the March 13 attack on the sprawling International Center for Peacekeeping and Security in Yavoriv, ​​a training base just 25 kilometers from the Polish border, bringing the conflict to the doorstep of the western security alliance.

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Regional Governor Maksym Kozytskiy said Russian planes fired about 30 rockets at the facility, adding that some were intercepted before hitting.

While Western countries have sought to isolate Russian President Vladimir Putin by imposing harsh economic sanctions and have supplied arms to Ukraine, the United States and its allies are hoping to avoid NATO being drawn into the conflict.

Britain has warned the incident marks a “significant escalation” in the conflict while White House national security adviser Jake Sullivan, speaking on CBS’s ‘Face the Nation’, said any attack on NATO territory would trigger a full alliance response.

President Joe Biden “has been clear, time and time again, that the United States will work with our allies to defend every inch of NATO territory and that means every inch,” Sullivan said.

The attack highlighted Russia’s intensifying assault on Ukraine, with heavy fighting reported in many parts of the country.

Amid the fighting, Ukrainian officials said Russia agreed to open more than 10 humanitarian corridors on March 13, including from the besieged port city of Mariupol, where the city council said 2,187 people had been killed. since the beginning of the invasion on February 24.

The International Committee of the Red Cross said on March 13 that hundreds of thousands of Mariupol residents “face extreme or complete shortages of basic necessities like food, water and medicine.”

“The corpses, of civilians and combatants, remain trapped under the rubble or lie in the open where they fell,” he added. said in a press release.

“In the name of humanity, this cannot go on”, Peter Maurer, president of the ICRC added in a tweet.

The United Nations said on March 13 that nearly 2.7 million Ukrainians fled to neighboring countries during the conflict.

The crisis prompted thousands of people to take to the streets in several cities across Europe, Russia and even Ukraine, where people marched past Russian soldiers in some towns waving Ukrainian flags and chanting slogans such as “Fascists are going home!”.

“Today is the biggest gathering in Kherson! In the eyes of the occupiers, there is despair, they are hiding behind hoods and looking away. Yes, they have weapons, but we are morally stronger “, said a post to a Twitter account set up for the videos of the city to be published.

In Russia, thousands of people gathered and shouted anti-war slogans despite a heavy police presence and threats of arrest from security officials.

According to OVD-Info, an NGO that monitors arrests during protests, 866 people have been arrested as anti-war protests erupted in at least three dozen cities across Russia.

Nearly 15,000 people have been arrested in Russia for protesting President Vladimir Putin’s decision to invade Ukraine,

Ukrainian President Volodymyr Zelenskiy, meanwhile, has again warned Russian forces that they will face a fight to the death if they try to occupy the capital, Kiev, whose inhabitants have again woken up to the sound of sirens from the raids. aerial.

“If they decide to carpet-bomb and simply erase the history of this region…and destroy us all, then they will enter Kiev. If that is their objective, let them in, but they will have to live on this earth in themselves,” Zelenskiy said on March 13.

The president, who has repeatedly appeared on social media from the capital, said some small towns no longer existed in the third week of the Russian attacks.

Despite intense fighting, Russian and Ukrainian negotiators reported progress in talks to resolve the crisis on March 13.

“We will not back down in principle on any position. Russia understands that now. Russia is already starting to talk constructively,” Ukrainian negotiator and presidential adviser Mykhaylo Podolyak said in a video posted online.

“I think we will literally get results in days,” he said.

Leonid Slutsky, a Russian negotiator, reportedly told the RIA news agency that the talks had made substantial progress.

“According to my personal expectations, this progress could turn in the next few days into a common position of the two delegations, into documents to be signed,” Slutsky said.

Neither side has said what the scope of a possible agreement might be.

In separate statements, Podolyak and Kremlin spokesman Dmitry Peskov said the talks were to resume by videoconference on March 14.

Three rounds of talks between the two sides in Belarus have focused mainly on humanitarian issues and led to the limited opening of some corridors for civilians to escape the fighting.