Putin supporters demanded a tough military response after 'five people were killed and ten wounded' in a Russian border city near Ukraine.
At least ten were wounded including a child according to reports.
Senior Russian senator Andrei Klishas accused Ukraine of shelling a residential area of Belgorod and demanded retaliation.
"The death of civilians and the destruction of civilian infrastructure in Belgorod are a direct act of aggression on the part of Ukraine and require the most severe - including a military - response,” he said.
Videos showed the carnage in the Russian city, some 25 miles from the Ukrainian border.
Supporters of Vladimir Putin and pro-Russian media called the Ukrainian attack an “act of terrorism”.
“It is obvious that this act of terrorism was committed in response to the liberation of Lysychansk by Russian troops,” reported Readovka.
"It is significant that each time the attacks on Russia and the liberated territories are becoming stronger, while there are no military or critical infrastructure facilities in the vicinity of the explosions.”
Ukrainian attacks were also reported on Kursk and Melitopol.
Readovka claimed that US-supplied HIMARS missiles could have been used, contrary to an agreement when the weapons were supplied to Ukraine.
The report stated: “The only way out of this situation is retaliatory strikes against the positions of the armed forces of Ukraine, along with command centres and warehouses with Western weapons.
“The terrorist state ‘Ukraine' must be completely demilitarised.”
Air defences, meanwhile, claimed to have shot down two incoming attacks, but a third got through, according reports.
Russian sources said 11 apartment blocks were damaged and 39 private houses in Belgorod.
Dozens of homes were damaged by blasts near the city which borders Ukraine, its regional governor claimed.
Ukrainian forces are said to have attacked a Russian military base in occupied southern Ukraine.
Vyacheslav Gladkov, Belgorod Governor reported a number of explosions in the city of nearly 400,000 some 40km (25 miles) north of the border with Ukraine.
At least 11 apartment buildings and 39 houses were damaged, including five which destroyed, Gladkov said on the Telegram messaging app.
Moscow has accused Kyiv of several attacks on Belgorod and other regions bordering Ukraine since Russia's February 24 invasion.
Ukraine has not claimed responsibility but described the incidents as payback and "karma" for Russia's
There was no immediate comment from Ukraine and Russian accounts could not be independently verified.
The General Staff of Ukraine's Armed Forces, however, said its air force had flown some 15 sorties "in virtually all directions of hostilities".
"About 20 units of enemy equipment and two field ammunition depots were destroyed.''
In the Russian-occupied southern Ukraine city of Melitopol, Ukrainian forces had hit a military base with more than 30 strikes on Sunday, the city's mayor said.