[Anchor Lead]
Ukrainian troops shelled the Russian-occupied Donetsk region, causing civilian casualties, the Russian side said.
While Putin is talking about the possibility of using nuclear weapons, Putin's ally Medvedev, deputy chairman of Russia's National Security Council, said he was ramping up production of new weapons.
This is reporter Kim Gwan-jin.
[Reporter]
In the pro-Russian-controlled Donetsk region of eastern Ukraine, Ukrainian forces are patrolling the streets and telling citizens hiding in abandoned houses that they are now free.
[Citizens of Donetsk, Ukraine: What's going on here?]
[Ukrainian troops: We've come to liberate our land.]
On the Russian side, the Ukrainian army fired multiple rockets into the center of Donetsk, killing one civilian and injuring three others, as well as a shopping center building, etc. said to have been destroyed.
Two people were killed and 10 wounded in a missile attack by Ukrainian forces in the southeastern Russian-occupied Melitopol, pro-Russian authorities said.
"We are increasing the production of the most powerful means of destruction," said Medvedev, deputy chairman of the Russian National Security Council, a close ally of President Putin, as Ukrainian forces began to recapture the Donbass region occupied by Russian forces.
"The next generation of weapons is intended to protect us from our enemies, including Europe and the United States," Medvedev said.
While President Putin mentioned the possibility of a nuclear attack, it is being interpreted as a hypersonic missile to deliver it.
Meanwhile, Germany supports the Patriot missile air defense system in Poland's border with Ukraine, which suffered damage from missiles during Russia's invasion of Ukraine.
The Bundeswehr plans to transfer three bombardment units to Poland after deciding on a location for the Patriot air defense system.