Waves of masked anti-government protesters hurl pavement stones and petrol bombs at lines of riot police, who cower behind their shields and then return fire with stun grenades, tear gas and plastic bullets.
Despite appeals for calm by opposition leaders, it is clear that the attacks on government forces have the support of many of the protesters and some opposition MPs - and this is an ominous sign for the coming days and weeks.
Still, it is important to bear in mind that, so far, the confrontations have been limited to a small square, just below the building of the country's cabinet of ministers.
In fact, although other cities have held their own demonstrations - and activists have reportedly been harassed and beaten in the country's east - the stand-off between President Viktor Yanukovych's government and the pro-European protests has primarily been focused on a small area in central Kiev.
The key events, as well as the future of the "Euromaidan" movement itself, are being played out around the capital's central Independence Square - where protesters continue to hold regular rallies and occupy a tent camp behind extensive barricades.
But it is equally vital to note that this battle, though restricted at the moment, may only be the beginning.
The conflict could move beyond its isolated location, especially if authorities decide to crack down on the movement, as they now are threatening to do.
With the clashes - which represent not only an escalation in the protest movement, but are also the worst in Ukraine's post-Soviet history - the country's political deadlock has moved even further into uncharted waters.
Ever since the crisis began (two months ago exactly, after President Yanukovych announced he was freezing negotiations with the European Union over a landmark trade and political treaty), it has been marked by a notable lack of any conceivable compromise that could break the impasse.
Whether the anti-government movement is justified in its demands or not, it is difficult to see how Mr Yanukovych can submit in any way to a scenario that spells no less than the end of his political life - or maybe worse.
Now with the clashes on Kiev's Hrushevskyy Street, another dangerous element has been added to the mix: uncontrolled far-right aggression.
Those attacking the riot police appear for the most part to be ultra-nationalists.
A group called the "Right Sector", which has helped man the Independence Square barricades, claims its members are helping in the fighting.
Protest leaders have tried to stop the violence, but to no avail.
Before the clashes broke out, boxing champion and opposition leader Vitali Klitschko called on the crowd to put down the chains and pipes that some were carrying.
He was booed and sprayed with a fire extinguisher.
The battle kicked off shortly afterwards.
Opposition heads have also tried to pin at least part of the fighting on outside "provocateurs".
But this only underlines their helplessness in the face of the escalating hostilities.
Outside forces or not, the fighting is widely supported in the anti-government movement - thanks to activists' rising anger at their leaders' failure to realise any of the protest demands, and the serious damage caused by riot police's beatings and plastic bullets.
Thousands gather nightly at the scene of the conflict to cheer on the combatants.
And the violence shows no sign of abating.
At times, the confrontation seems almost medieval - complete with a catapult (albeit one with the modern touch of its own Twitter account), fighters bearing home-made shields with crusader-like crosses on them, and robed priests praying with icons to the side.
But, make no mistake: Hrushevskyy Street is a very serious zone of combat - one where anger on both sides is mounting with each wave of attacks.
Now, the government appears to be moving in to end the conflict.
According to President Yanukovych, the country's security and stability is at stake.
"When peaceful actions are turning into mass unrest, accompanied by riots and arson attacks, the use of violence, I am convinced that such phenomena are a threat not only to Kiev but to the whole of Ukraine," he said in his video address on Monday.
The only question is, what method will he use?
The president said he would employ all "legal" means to restore order.
Thanks to the new "anti-protest" laws, which helped spark the violence and will officially go into effect on Wednesday, the lawful tools that the government has at its disposal are many.
Officials can deal with protesters with the scalpel of individual arrests, or the blunter instrument of a general crackdown.
All of which points to the likelihood that Ukraine's ongoing political crisis will not end soon and could spiral even further out of control.
Two sides are locked into their respective positions, with no solution in sight, violence is escalating and an aggressive faction is gaining the upper hand.
Meanwhile the government is set on ending the unrest, which may increase even more the backlash.
A recipe for further turmoil, at the very least.
Source: BBC News