Parliament heard that Pshonka and Klimenko had initially been detained at an airport in the eastern town of Donetsk but escaped after armed men entered the VIP lounge and began shooting.
"An investigation has been opened and an investigating-operational group is working for the detention of these people to bring them to trial," said Oleh Makhnytsky, acting prosecutor general.
Under pressure, too, from the Maidan—the name given now to the protest movement that brought Yanukovych down—the new leaders said police and others who had shot at people or given orders to shoot would be brought to book.
"Since yesterday, operational measures have been going on to stop criminals who fired at people or gave the orders (to shoot) from leaving the territory of Ukraine. Any person who gave the order to fire must be detained," said Nalivaychenko.
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Acting interior minister Arsen Avakov said an investigation had been opened up to identify those who had exceeded their powers during the mass protests in Ukraine. Thirty possible suspects had already been identified among police, he said.
Though Avakov said police were investigating "grave crimes ... by former state leaders", no order was given for the detention of Yanukovych himself.
His precise whereabouts were unknown on Sunday, though he may be in his stronghold in the eastern city of Donetsk.
Border guards said on Saturday he had tried to leave Donetsk on a chartered plane for an undisclosed destination, but after being refused permission, his security guards drove him away by car.
Though Parliament did not issue an order for his arrest, deputies found a way of hurting him nonetheless—ruling that the 140-hectare estate outside Kiev where he lived in sumptuous style should be returned to the state within 10 days.
In parliament, his support finally collapsed, with Oleksander Yefremov, until Sunday a dutiful head of the party faction, now denouncing his former master for issuing "criminal orders" that brought deaths, empty state coffers, huge debts and "shame on the Ukrainian people".