the population of eastern ukraine. >> jones: i went back to see oleg's leader, right sector's dmytro yarosh. the u.n. has called for an investigation into the killing of pro-russia demonstrators. still, yarosh was planning new attacks on the separatists. >> our authorities are acting indecisively. two months ago it was possible to avoid this by taking certain people under control, containing the pro-russian activity, so that none of this would happen. now the situation has picked up momentum. weapons have been delivered there, so they have the means to fight. the situation is getting worse and worse. (shouting, gunfire) >> jones: in fact, on the day i saw him, yarosh had sent his right sector fighters into the eastern town of mariupol alongside the ukrainian army. they wanted to take back the police station from the pro-russia separatists. >> this morning we began the attack and three of our men have been killed, and some were wounded. it's a full-blooded fight. we've sent in armored vehicles. >> jones: they were accused of firing indiscriminately. (shouting) 21 people were killed that day.