Major-General Oleg Mityaev, 47, commander of the army s 150th motorised rifle division, died fighting around the besieged city of Mariupol, Ukraine has claimed.
The group, lead by Major Viktor Blyudin, was a reconnaissance team located in the forest near to the town of Sribne in the southern part of Chernihiv oblast.
The bulk of Russian ground forces are now around 15 miles from the centre but elements of the large column have dispersed in a bid to encircle the city.
Vladimir Putin has ordered his troops to release radioactive waste at the nuclear site which he plans to blame on Ukrainian saboteurs , Kyiv officials have warned.