Hundreds of supporters freed former Georgian president Mikheil Saakashvili from a Ukrainian police van Tuesday after he was arrested by the country's security services on criminal charges.
The dramatic showdown between hundreds of Saakashvili supporters and the Ukrainian authorities followed a long-running feud with President Petro Poroshenko who stripped the 49-year-old politician of his passport.
In September, Saakashvili, who was a regional governor in Ukraine, defied the authorities and forced his way back into the conflict-riven country with the help of his supporters. He has led protests against his government since October.
On Monday morning, police raided Saakashvili's flat, prompting him to climb onto the roof of his central Kiev building and address supporters below before officers led him down into the vehicle.
The security service said Saakashvili was arrested on charges of assisting criminal organisations.
Ukraine's general prosecutor Yuriy Lutsenko accused Saakashvili and his allies of receiving $500,000 (420,000 euros) from Russian sources to fund the protests against the Ukrainian government.
After Saakashvili's detention several hundred people gathered around the van carrying the politician and prevented it from moving before freeing the politician from inside.
After emerging from the van with a handcuff on one hand, Saakashvili urged the crowd to march to the Ukrainian parliament and demand the impeachment of the president.
"There are millions of us, we are very strong," he said.
Speaking earlier from the roof, he accused Poroshenko of a being a thief and "a traitor to the people of Ukraine."
"I call on all decent Ukrainians to take to the streets and drive out these thieves... I call on Ukrainians not to allow me to be abducted, I appeal to the people of Kiev not to allow lawlessness."
Saakashvili fell out with Poroshenko over accusations that Kiev was failing to make good on the fight against corruption.
Saakashvili hopes his own political party will grab seats from the president's increasingly unpopular group in polls set for 2019.
"This morning in the Ukrainian capital Kiev, my husband was taken by government troops from his home and moved by force into a minivan that was subsequently blocked by hundreds of his supporters, growing already into the thousands," Saakashvili's wife Sandra Roelofs said earlier on her Facebook page.
"Time will show where this leads to, we pray it will stay peaceful!"
- Kremlin 'surprised' -
President Vladimir Putin's spokesman said the Kremlin was "once again surprised by Kiev and once again surprised by Saakashvili".
Asked to comment on the situation, Putin spokesman Dmitry Peskov said, "We are not used to responding to the statements of people sitting on roofs."
Carl Bildt, the co-chair of the European Council on Foreign Relations, said the news of the arrest was "disturbing".
"Political arrests will radically diminish the country?s credibility in the West. That's a security issue at the end of the day," the former Swedish prime minister said via Twitter.
Saakashvili is credited with pushing through pro-Western reforms in his native Georgia which he led from 2004 to 2013 after rising to power during the so-called Rose Revolution in 2003.
In the wake of the pro-Western revolution in Kiev he moved to Ukraine in 2015 to work for the country's authorities as governor of the key Odessa region on the Black Sea, before falling out with Poroshenko.
A conflict between Russia-backed fighters and Ukrainian troops has killed more than 10,000 people since 2014, when pro-Russian forces declared parts of eastern Ukraine independent following Moscow's annexation of Crimea.