A Ukrainian pilot has been found guilty in Russia of charges relating to the deaths of two Russian journalists.
Nadiya Savchenko was sentenced to 22 years in jail after being convicted of directing artillery fire which killed them in eastern Ukraine in June 2014.
She burst into a folk-style protest song in the courtroom as she was finally pronounced guilty after the judge's two-day reading of the verdict.
She denied all the charges and her case has become internationally notorious.
Ukraine would never recognise the "so-called" verdict, President Petro Poroshenko said, describing the trial as "infamous".
In a statement (in Ukrainian), he added that he was ready to exchange Savchenko for two Russian soldiers detained in Ukraine for "their participation in the armed aggression" against the country.
Savchenko has become a national hero - elected as a Ukrainian MP while in detention - and scuffles were reported in the courtroom after members of a Ukrainian delegation unfurled a national flag.
Her lawyer, Nikolai Polozov, told journalists that she would "not appeal against this illegal verdict", in which Savchenko was also found guilty of illegally crossing the border into Russia and the attempted murder of civilians.
"She is an iron person, she has an iron will," Mr Polozov said, according to AFP news agency.
At the scene: Sarah Rainsford, BBC News, Donetsk, Russia
This tiny Russian border town was under lockdown for the final hours of the trial. Dozens of Cossacks were drafted in to line the streets alongside heavily armed police. At a security check outside court, officers checked bags and scanned journalists' notebooks for "forbidden" texts.
Inside, Nadiya Savchenko was a picture of calm - until the verdict. As the judge pronounced her guilty she broke into deafening song to drown him out. But the result was no surprise to her defence team, nor the fact that the judge dismissed all the evidence they presented.
A few half-hearted protesters gathered outside waving signs declaring Savchenko a "war criminal" and in court three young men suddenly displayed T-shirts with the faces of the Russian journalists she is accused of killing.
They were outnumbered, though, by politicians from Kiev and supporters of Savchenko. As her sentence was handed down - and she yelled abuse at the judge - some pulled out the Ukrainian flag and burst into their national anthem before being bundled unceremoniously out of court by bailiffs in balaclavas.
Her lawyers say Savchenko has threatened to go on a dry hunger strike (refusing all fluids) on 6 April, 10 working days after the verdict, in order to get sent home "dead or alive".
Russian prosecutors said Savchenko had been driven by "political hatred".
Western politicians and intellectuals have been among those calling for her release, echoing her lawyers' descriptions of the process as a show trial and a farce.
Human Rights Watch condemned the trial as unfair, complaining that the court had "refused to admit crucial defence evidence and consistently rejected important defence motions, making it impossible for her legal team to effectively challenge the allegations against her as fair trial standards require."
The hearing took place in the southern Russian town of Donetsk, not far from the Ukrainian border.
There was confusion on Monday at the start of the court session, when Russian state media announced the guilty verdict prematurely.
Savchenko, a military pilot by training, was accused of having acted as an artillery spotter on the ground.
Her lawyer has argued that phone records prove she was captured by rebels before the attack, and that she was trying to reach fighters from her volunteer force who had been wounded in an ambush.
Savchenko's capture - or as she puts it, her kidnapping - contributed to the deterioration in Russia-Ukraine relations since 2014.
Moscow annexed the Crimea peninsula in March 2014 after an unrecognised referendum on self-determination, and is accused of covertly supporting separatist rebels in the bloody conflict in the eastern Donetsk and Luhansk regions of Ukraine.