Fierce battles in Ukrainian cities, and Russian bombing destroys the world's largest cargo plane.
Several explosions resounded after midnight in the Ukrainian capital, Kiev, and violent clashes took place north of the city, which Russian forces are trying to control on the fifth day of the attack.
The General Staff of the Ukrainian Armed Forces described Sunday as "tough" for the army, saying that Russian forces "continue to bombard in almost all directions."
The General Staff added - in an English-language post on Facebook - that members of the Defense Force at the Vasylkiv Military Air Base (southwest of the capital, Kiev) are resisting artillery shelling and Russian attacks.
In conjunction with the clashes in the capital, the Ukrainian parliament unanimously approved the imposition of a state of emergency in the country, with the intensification of battles between the Russian forces and the Ukrainian army in a number of cities, and both parties announced heavy losses to the other.
He stated that Parliament's approval to impose a state of emergency came in response to an earlier appeal by the National Security and Defense Council to impose a state of emergency in the country.
According to the state of emergency, the movement of vehicles will be restricted, government forces will be given the right to inspect cars, and the protection of public order and government facilities will be enhanced, and the decision to impose a state of emergency prohibits the organization of mass demonstrations.
These developments come at a time when Russia admitted on Sunday the fall of its soldiers in its war on Ukraine, and hundreds of its military vehicles were advancing towards the capital, Kiev, while the North Atlantic Treaty Organization (NATO) criticized Russia after putting the "nuclear deterrent" forces on alert.
The Russian news agency (Interfax) quoted the Russian Defense Ministry as saying that there were dead and wounded among its forces during the war on Ukraine, and that several Russian soldiers had been captured by the Ukrainian forces.
Satellite images published by the American company "Maxar" showed a 5-kilometre-long Russian military convoy heading towards the Ukrainian capital, Kiev.
According to a company statement, the Russian military buildup included hundreds of military vehicles, including tanks, fuel vehicles, armored vehicles and artillery. He pointed out that the military convoy is now 64 kilometers from Kiev.
And the Ukrainian public group "Okroboronprom" announced on Sunday that the world's largest Antonov 225 aircraft was destroyed in Russian strikes on an airport near Kiev, which is witnessing fierce battles.
The group said in a statement that "the Russian invaders destroyed the most prominent Ukrainian planes" at the Antonov Airport in Gostomel, where the plane was undergoing repairs, and indicated that its restoration would cost more than 3 billion dollars and would take a long time.
This aircraft is unique in the world; Its length is 84 meters and it can transport up to about 250 tons of cargo at a speed of up to 850 kilometers per hour. That is, "dream" in Ukrainian.
"Russia has destroyed Maria, but it will not be able to destroy our dream of a strong, free and democratic European state," Ukrainian Foreign Minister Dmytro Kuleba said on Twitter. "We will win."
The announcement came at a time when Gostomel Airport has witnessed violent clashes since the start of the Russian war on Ukraine last Thursday, and the Russian army is trying to control this strategic infrastructure.
On the other hand, Oleg Senegubov, a local official in Kharkiv, said on Sunday that the city had returned to the control of Ukrainian forces, a few hours after he announced the arrival of the Russian army to the city center.
"Kharkiv is under our complete control," Senegubov wrote on social networks, stressing that the process of "expelling the enemies from the city" was underway.
According to him, "the Russian enemy is completely frustrated", and abandoned his vehicles and groups of soldiers who "surrendered to the Ukrainian army".
Reuters quoted Oleksiy Aristovich, an adviser to the Ukrainian president, as saying that their forces destroyed half of the Russian vehicles that entered Kharkiv.
Aristovich said on Sunday that the situation "has not changed significantly in Ukraine, we control the lands west of Kiev and the Russian forces have not advanced south."
Kharkiv, which has a population of 1.4 million, is the main city in northeastern Ukraine, close to the Russian border and the lands controlled by pro-Russian separatists in Donetsk and Lugansk.
In a related context, Kremlin spokesman Dmitry Peskov said that the leaders of the so-called "Republics of Donetsk and Luhansk" requested military support from Russian President Vladimir Putin in the face of what he described as "Ukrainian aggression" against the Donbass region.
The separatist forces loyal to the Russians say that they have taken control of several cities in the Donetsk region (eastern Ukraine) and are continuing the battles with the aim of controlling the entire region.
The separatist forces in Lugansk also stated that they had captured two cities on the dividing line, heading towards the Ukrainian forces.
In the Sumy region (northeast of the country), battles are still taking place between Russian and Ukrainian forces.
In the south, Russian forces are trying to take control of Kherson, starting from the adjacent Crimea, which they have controlled since 2014.
The Ukrainian Ministry of Defense also stated that the city of Odessa on the Black Sea was under fire.
In the capital, Kiev, the city's mayor, Vitali Klitschko, said that there are no Russian forces in the Ukrainian capital, and Klitschko added - on his channel on Telegram - "But our army, law enforcement agencies and regional defense continue to detect and neutralize saboteurs."
He explained that 9 civilians and 18 soldiers have been killed since the start of the attack on the capital, and the Ukrainian forces said that they destroyed a winged missile coming from the Belarus side.
The Ukrainian Ministry of Health stated that 352 civilians - including 14 children - have died in the Russian attack on Ukraine so far.
The Ukrainian army is trying to repel incursion attempts from different axes of the Russian army, which is superior in number and equipment, and said that it thwarted an air landing of Russian forces in the Black Sea region.
On Sunday, the Ukrainian Defense Ministry said that about 4,300 Russian soldiers have been killed since Russian President Vladimir Putin announced - at dawn last Thursday - the start of the military operation against Kiev.
This outcome has not been independently verified, noting that Moscow has not yet officially announced any census of its losses in the battles.
According to estimates by Western intelligence officials, Russia was surprised by the ability of the Ukrainian forces to repel its army, which has not yet made rapid progress as he had hoped.
A senior official at the US Department of Defense (Pentagon) said that Putin had brought a third of his combat forces that he had mobilized into Ukrainian territory, and added that there were no indications that Russian forces had taken control of any of the Ukrainian cities.
The official stressed that his country sees a decline in the momentum of the Russian forces, which are facing strong resistance from the Ukrainian forces.
On Sunday, Ukrainian President Volodymyr Zelensky called on foreigners wishing to help his country confront Russian military operations to go to Kiev's embassies around the world and register their names to join an "international squad" of volunteers.
While Zelensky stressed that the Ukrainians were brave enough to defend their country on their own, he saw that the Moscow attack "is not just a Russian invasion of Ukraine, but the beginning of a war against Europe."
He called on foreigners wishing to join the battle to communicate with the military attaches in the embassies of Ukraine.
On the other hand, the Russian Defense Ministry announced on Sunday the destruction of 1,076 Ukrainian military sites since the start of the military operation last Thursday.
The ministry stated - in a statement - that its forces launched new strikes, with long-range precision weapons, using winged missiles from the air and sea, against the military infrastructure facilities of Ukraine.
The statement indicated that among the targeted facilities were 23 control points and communications centers for the Ukrainian forces, and 31 pieces of the "S-300", "Buk M-1" and "Osa" systems. ) for anti-aircraft missiles and 48 radar stations, according to what was reported by Russia Today.
The Russian forces also shot down 8 Ukrainian combat aircraft, 7 helicopters, 11 drones, in addition to two Tochka-U tactical missiles, according to the statement.
Russia's nuclear deterrent
In return, President Putin ordered his military command to put Russia's deterrent forces (in reference to units that contain nuclear weapons) on high alert, citing hostile statements by NATO leaders and economic sanctions against Moscow.
Putin said - on state television - "As you can see, Western countries do not take unfriendly measures against our country only in the economic dimension; I mean illegal sanctions that everyone knows very well, but also that senior officials of the main NATO countries allow themselves to make hostile statements about our country."
For his part, NATO Secretary-General Jens Stoltenberg said on Sunday that Putin's move to put Russian forces on high alert is dangerous and irresponsible, adding to the Russian leader's aggressive pattern with regard to Ukraine, as he put it.