For now, the guns have gone quiet in Kyiv, amid a fragile truce between government troops and Euromaidan protesters.
But photographs making the rounds in Ukraine have raised questions about what kind of ammunition were used in the January 22 deadly clashes, when two protesters were shot dead -- at least one reportedly by conventional bullets.
One of the photographs shows a typical shotgun shell, which can be filled with a range of projectiles, including rubber pellets.
Another shows a spool-shaped metal slug, approximately 2 centimeters in length, that had reportedly been shot minutes before by police.
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In its shape and dimensions, the bullet appears to resemble an all-steel bullet commonly known as a Blondeau slug, which was developed during World War II to disable vehicles because of its ability to penetrate engine compartments.
A similar shape can be seen in some hunting ammunition.
It is not clear that the Kyiv bullets, which are far smaller than most hunting slugs, are considered lethal ammunition. One Kyiv-based journalist noted that the bullets "will knock you down, even if they don't always penetrate."
Still, the presence of any form of metal bullets appears to contradict continued assertions by the Interior Ministry that its troops are carrying firearms loaded only with rubber bullets.
Troops have been armed with truncheons, tear gas, and flash grenades to fight back protesters defying a new Ukrainian law, in effect since January 22, banning demonstrations that block government buildings.
Violent clashes broke out as the law came into effect, resulting in hundreds of injuries, and at least three deaths, including two by gunfire.
The first identified victim, Serhiy Nihoyan, reportedly sustained four shots, including to the head and neck. The "Kyiv Post" cited Oleh Musiy, the coordinator of medical services for the Euromaidan demonstration, as saying it was "impossible" that Nihoyan's fatal injuries were caused by rubber bullets.
There has been no official information released about the type of bullets that killed Nihoyan.
The second victim, Mikhail Zhyzneuski, reportedly died of a gunshot wound to the heart. A friend said he had witnessed Zhyzneuski being shot with a Makarov pistol, which can be loaded with either rubber or conventional bullets.
Rubber bullets are designed as general deterrents, with an inaccurate trajectory but considerable force. A rubber bullet shot at a distance of 20-50 meters can cause blunt trauma. The U.K.-based Omega Research Foundation says there are "many" recorded instances of people being killed by rubber bullets shot at close range.
Yulia Gorbunova of Human Rights Watch (HRW) said from Kyiv that the organization had received numerous reports of protesters being injured after being struck in the face and head by rubber bullets, particularly during the most intense confrontations January 22 on Kyiv's central Hrushevskoho Street.
Gorbunova said HRW had received no information about the ammunition that killed either Nihoyan or Zhyzneuski. But she said the group had received one confirmed report of a protester being shot with a conventional bullet.
"In terms of real bullets, there is one incident we're aware of. We talked to a doctor from the emergency department of a local hospital who told us that they had a man brought in yesterday with a bullet wound to his chest," Gorbunova said.
"He was found on Hrushevskoho. He's currently in poor condition and he's unconscious, so we weren't able to actually talk to him. But the doctor said that it was a real gunshot wound."
Gorbunova says Kyiv police are formally authorized to use lethal force against protesters in instances of extreme violence. But she adds that the use of conventional bullets, or excessive use of rubber bullets, would clearly constitute disproportionate use of force.