Images and video uploaded from the city of Donetsk in eastern Ukraine Monday morning show multiple casualties from what appears to have been a missile strike on the city.
Donetsk is held by Russian-backed separatist forces and is the capital of the so-called Donetsk People's Republic (DPR).
The videos, geolocated by CNN, show that there were at least several fatalities on a main street in the city center as well as a large number of injured.
Remnants of the missile can be seen at the scene. Where it came from and who fired it are still unclear.
“At the moment, we can talk about the largest number of civilian casualties as a result of a single strike," the leader of the DPR, Denis Pushilin, told Russian television.
"Around 20 people [died], but the number is being updated” he told Russia 24, calling it a “war crime.”
A local news agency quoted the Headquarters of the Territorial Defense of the DPR as giving the same figure.
The People's Militia of the DPR accused the Ukrainian side of launching the missile, saying, “The Ukrainian armed formations once again used the tactical missile system 'Tochka-U' in the residential areas of Donetsk, in order to [cause] genocide [to] civilians and destroy important civilian infrastructure in the capital of the Republic."
The Ukrainian armed forces have the Tochka missile but it has also been used by Russian and separatist forces in the past. CNN has reached out to the Ukrainian Defense Ministry for comment.
Pushilin separately told the Russian state television network Russia-1, "We managed to shoot down the tactical missile system Tochka-U , but even the wreckage did so much damage."
"The worst is the loss of civilian lives. People were standing in line for the ATM, at the bus stop," he added.
Separately, the health ministry of the DPR spoke of 23 injured being admitted to hospital.