Vladimir Putin's troops are inching closer and closer to Kyiv as the battle for the capital is underway.
The Russian military is now believed to be just three miles from the city's limits, a senior US defence official said.
A 40-mile long convoy of Russian tanks has been slowly advancing towards the capital as ambush attempts and shelling have been seen on the outskirts.
Russian troops launched two attacks in the area - one in the western city of Irpin and another on the east side of Brovary.
Video of the attack in Bovary shows Russian tanks being ambushed with heavy artillery before turning back.
Colonel Andrei Zakharov, commander of the tank regiment, was also killed in the ambush according to the Ukrainian defence ministry.
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Vadym Denysenko, an adviser to Ukraine's interior ministry, said his forces also stopped the attack in Irpin.
In an update today, the Ukrainian military said it had stopped Russia's attempt to cross the Irpin River in the town of Moshchun.
Denysenko said: "The night was quite difficult, but in general we can say that the Ukrainian army counterattacked near Kyiv.
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"There is no further detailed information yet."
Putin's efforts to surround the capital continued today as more fighting has been reported on the southwest side of Kyiv.
A full-scale assault on the Ukrainian capital could be on the horizon as there are fears Putin could launch similar airstrikes as he did on the city of Mariupol and Kharkiv.
In Mariupol, a maternity hospital was hit and killed three, including a six-year-old girl.
President Volodymyr Zelensky, who is still in Kyiv, today said his "heart breaks at what the occupants have done with our cities, our country, and at what they want to do to our people",who he said needed "urgent help".
Kyiv mayor Vitali Klitschko said today that the capital has been turned into a fortress ahead of the Russian assault.
He said in televised remarks: "Every street, every house is being fortified, the territorial defence is joining.
"Even people who in their lives never intended to change their clothes, now they are in uniform with machine guns in their hands."
Troops are warning civilians not to stray beyond the outskirts of the city because Russian vehicles had been spotted just a few miles away.
If Putin's troops encircle Kyiv, they could shell it as they have done to Mariupol, Kharkiv and Chernihiv.
Ukrainian officials say Mariupol continues to be surrounded by Russian forces but is still in Ukrainian control.
They said Ukrainian fighter jets and anti-aircraft missile units destroyed four Russian Su-25 attack jets and two Russian helicopters over the past 2 days.
It comes as chilling photos from Mariupol showing corpses being discarded in mass grave sites as the death toll in the city grows.
This week it was revealed more than 1,200 people have died in the port city, formerly the home of nearly half a million people, since the start of the Russian invasion.
Described by rescuers as a humanitarian crisis, authorities have ordered workers to dig 25 metre long trenches as morgues are at breaking point.
In tragic scenes, they were seen making the sign of the cross as the dead- wrapped in an old carpet- are pushed into the makeshift mass graves.
Forty bodies were dumped in the trench in the cemetery on Tuesday, followed by 30 more on Wednesday. They were said to be both civilians and soldiers
No family members were seen at the gravesite to say goodbye to their loved ones.
Ukraine estimates that Russia has lost some 12,000 troops in the fighting, along with 335 tanks, 1,100 armoured personnel carriers, 500 vehicles, 81 helicopters and 49 planes.
Moscow has not given an accurate figure.
