A few hours before he was detained, Mr. Saakashvili had called for weekend protests against Mr. Poroshenko in Independence Square, an area in Kiev known as Maidan that was the center of the earlier demonstrations against Mr. Yanukovych. Mr. Lutsenko, the prosecutor general, this week accused him of receiving $500,000 for his political activities from a fugitive Ukrainian businessman close to Mr. Yanukovych, who has lived in exile in Russian Federation since his ouster.
He was later freed from police custody by a crowd of his supporters.
On Tuesday, he was dragged from his home in Kiev and arrested. Saakashvili then re-entered the country illegally and staged multiple rallies in the capital demanding the president be impeached.
Ukrainian President Petro Poroshenko denied on Friday interfering with the work of law enforcement bodies investigating corruption and he urged such agencies to refrain from playing politics.
General Prosecutor Yuriy Lutsenko, who says Saakashvili is suspected of assisting a criminal organization, said the opposition leader had been detained by police in Kyiv and was in a temporary detention facility.
MI congressman John Conyers accused of sexually harassing staffer and her cousin
Conyers, who was first elected in 1964, easily won re-election previous year in the heavily Democratic 13th District. Conyers, 88, was hospitalized last week for a stress-related illness after returning home from Washington, D.C.
"Mikheil Saakashvili won yesterday, and he won not when the Ukrainian people released him from the police minivan, but when he was arrested".
If found guilty, he could face up to five years in jail. He claims the accusations are politically motivated.
"I assured the President that the IMF stands ready to continue to support Ukraine, along with other global partners, in the fight against corruption and encouraged the authorities to accelerate the implementation of reforms", she said.
Saakashvili became a regional governor in Ukraine in 2015 at Poroshenko's invitation but they later fell out.