The two Ukrainians accused of planting the car bomb that killed journalist Pavel Sheremet in 2016 are known to the public for their roles in the war against Russia-backed forces in the country' s east. One was singled out for praise by then-President Petro Poroshenko in 2017.
On December 12, law enforcement officials named five people they said have been detained on suspicion of involvement in the killing of Sheremet, who died when an explosive device affixed to the bottom of the car he was driving went off at a Kyiv intersection as he was heading to a studio to host his radio program on July 20, 2016.
A Belarus-born Russian citizen who had made Kyiv his home, Sheremet was a muckraking reporter whose death underscored concerns of a climate of impunity for attacks on journalists and others challenging the powerful in Ukraine.
Poroshenko' s government faced persistent criticism over the perceived lack of progress in solving the case. Shortly after taking office in May, President Volodymyr Zelenskiy renewed the push for results in the investigation.
At a press conference to announce the developments, deputy national police chief Yevhen Koval said that Sheremet's killing was aimed at destabilizing the "social and political situation in Ukraine."
"This is the first step in solving this crime, because only those who planned and committed the murder have been identified," Prosecutor General Ruslan Ryaboshapka said. "The country still needs to hear…who was the initiator and organizer of this terrible murder."
These are the suspects:
Officials allege that Andriy Antonenko, a musician who has fought in the more than five-year war in the Donbas, and his friend Yulia Kuzmenko, a doctor who has volunteered to help Ukrainian troops fighting in the conflict, planted the bomb -- which authorities said was made by one of their suspected co-conspirators.
Antonenko, a muscular conflict veteran whose body is covered in tattoos, authored a song whose title translates as Came Quietly, Left Quietly, and which has been described as the unofficial anthem of the Special Operations Forces, a branch of Ukraine's military.
"From the first days of the war, Andriy assisted the army as a volunteer. The fighters of the Special Operations Forces (SOF) know Andriy well. And the song that he dedicated to the fighters of the SOF is known by heart," Poroshenko said in a Facebook post on July 29, 2017 that linked to a video of the song.
The video features a group of Ukrainian fighters making a fictional sneak attack on an enemy.
Antonenko first came to the Donbas front to perform for government forces. He began volunteering before joining the SOF, making the rank of sergeant.
Born in Kyiv in 1971, Antonenko initially pursued a music career as rock flourished in the glasnost era before the Soviet collapse. He joined the thrash-metal group ADEM as a singer and guitarist before joining another band, Daz Machine, and in 2003 formed his own group, Riffmaster.
Antonenko's Instragam feed -- in addition to everyday selfies -- is filled with photos and videos of himself playing the guitar, often in military gear, and lifting weights.
A recent post features a drawing of a figure that looks like Russian President Vladimir Putin lying on the ground with bullet holes under the words "mission complete."
Police said some of Antonenko's social media posts helped them identify him as one of the shadowy figures seen in surveillance-video footage approaching the parked car in which Sheremet would be killed the following day. The clothing of one of the people in the video matched clothes in Antonenko' s posts, they said.
Antonenko lived near Sheremet, the police said.
As officers arrived at his home on December 12, Antonenko took to Facebook to inform his friends and followers.
"I have been charged with the murder of Sheremet. Right now. Here in my courtyard. They will do a search. Help!" Antonenko wrote in the post. He has denied any involvement in the killing.
Among Antonenko's Facebook friends is Kuzmenko, a 40-year-old doctor at a children's hospital in Kyiv. Kuzmenko volunteered to treat protesters who thronged Kyiv's central square and faced off against law enforcement during the Euromaidan uprising that pushed Moscow-friendly President Viktor Yanukovych from power in February 2014.
Kuzmenko ran for a seat in the Kyiv city council in May 2104 but did not win a seat. The war in the Donetsk and Luhansk provinces had broken out in April, and she volunteered to help the military and families impacted.
Her Facebook page is filled with photos of herself in the field with soldiers and pro-Kyiv fighters, including some from Right Sector, a far-right Ukrainian paramilitary group.
Her lawyer, Vlad Dobosh, said in a Facebook post that she was innocent.
Vladyslav And Inna Hryshchenko
Kuzmenko had recently been attending the trial of Vladyslav and Inna Hryshchenko, a couple who were detained earlier this year on charges of attempting to kill a businessman in western Ukraine by blowing up his car. The bomb fell off the car and failed to go off, authorities say.
The Hryshchenkos are now among the five suspects in Sheremet's killing. Law enforcement authorities said that the bombs used in the two cases were similar and that Vladyslav Hryshchenko is an explosives expert with six past convictions for extortion and robbery.
The two met while fighting among Right Sector forces in the province of Donetsk and later married. Inna Hryshchenko's arrest in November, two months after her husband was taken into custody, attracted media attention.
"I support Inna Hryshchenko and Vlad Hryshchenko. In the wildest dreams of the authorities we are all gone -- the Maidan protesters, fighters, volunteers, etc., -- the bearers of the memories of the past six years who have the right to spit in the eyes of those who are betraying Ukraine right and left," Kuzmenko wrote in a Facebook post shortly after Inna Hryshchenko' s arrest. The post featured a selfie of the two of them sitting together at what appears to be a restaurant patio.
The fifth suspect, servicewoman Yana Dugar, is accused of aiding in Sheremet's killing by taking photographs of security cameras near his home.
Dugar, 26, has served as a nurse in a paratrooper battalion.