A former Russian parliamentarian named Denis Voronenkov, who fled Russia last October and has criticized President Vladimir Putin's government, was killed in Kiev on Thursday, in an apparent assassination that Ukrainian President Petro Poroshenko is reportedly calling "state terrorism."Voronenkov, 45, had just left the Premier Palace hotel when he was shot twice in the head on a sidewalk along a busy street in Ukraine's capital, according to the Kyiv Post. Citing police, the newspaper adds that both Voronenkov's bodyguard and the attacker were wounded and in the hospital.The killing has the "handwriting" of the Russian special services, Poroshenko said in a statement Thursday. According to a translation by Reuters, he said Voronenkov's murder was "an act of state terrorism on the part of Russia, which he was forced to leave for political reasons."Responding to those accusations, Russian presidential spokesman Dmitry Peskov said, "We believe that all speculations about a Russian connection are absurd," according to state-run Tass media. He also said Ukraine "had proved unable to take care of Voronenkov's security," the outlet reports.Poroshenko said Voronenkov was a key witness in Ukraine's inquiry into former Ukrainian President Viktor Yanukovych and Russian military involvement in the country.When he fled Russia, Voronenkov did so along with his wife, Maria Maksakova, who is also a former lawmaker. She was seen at the site of her husband's killing today, being restrained by police and emergency workers.Here's how Radio Free Europe recently described Voronenkov: