According to information from Kyiv, bitter fighting raged along the entire war front in eastern Ukraine on Saturday.

There were conflicting reports on the situation in Lysychansk, which was particularly hotly contested. The Ukrainian army rejected reports of success from pro-Russian separatists, saying that the city was now completely surrounded.

Meanwhile, Belarusian ruler Alexander Lukashenko accused Ukraine of launching rocket attacks on his country.

Regarding the situation in eastern Ukraine, Ukrainian head of state Volodymyr Zelenskyy said in his daily video address on Saturday evening: "The fierce fighting along the entire front line continues."

A Ukrainian army spokesman said of the fighting around Lysychansk that the city was "not surrounded and still under the control of the Ukrainian army".

A few hours earlier, the pro-Russian fighters had announced that they had "completely encircled" Lysychansk.

Together with Russian troops, "the last strategic hills" were conquered today, a separatist representative told the Russian news agency Tass.

Bitter fighting for the strategically important city of Lysychansk

Lyssychansk has been hotly contested for days.

The neighboring town of Sievjerodonetsk was captured by Russian troops a week ago after weeks of fighting.

Both cities belong to the Luhansk region, one of the two sub-regions of the Donbass.

Should Russian troops also capture Lysychansk, they could then target Kramatorsk and Sloviansk in Donetsk, the second Donbass sub-region.

Sloviansk was recently under heavy rocket fire.

At least four civilians have been killed and 12 others injured since Friday morning, according to Governor Pavlo Kyrylenko.

A woman was killed in her garden in an attack on a residential area in Sloviansk on Friday evening, a neighbor told AFP news agency.

Her husband was injured and the entire neighborhood was littered with rubble.

Sloviansk Mayor Vadym Liakh accused Russia of using cluster munitions in the attack.

This is outlawed by international treaties, which Moscow has not signed.

Russia: At least three dead in Belgorod

Explosions in the Russian city of Belgorod near the border with Ukraine have killed three people, according to the region's governor.

According to the Tass agency, Vyacheslav Gladkov wrote this on Sunday in the Telegram news service.

Four other people were injured, including a 10-year-old child.

In addition, 50 houses were damaged.

The causes of the incident are being investigated and the air defense system is expected to be activated.

The information could not be independently verified.

Ukraine: Russia attacked Snake Island with phosphorus shells

The Ukrainian army also accused the Russian armed forces of having attacked the Snake Island in the Black Sea with phosphorus bombs.

The island had been shot at twice by SU-30 planes with the internationally banned weapons, army chief Valeriy Saluschny explained in the messenger service Telegram.

The island is considered a strategically important post for monitoring sea routes in the north-western Black Sea.

The Russian army had occupied Snake Island for four months, but then surprisingly withdrew from it on Thursday.

Phosphorus weapons are not explicitly prohibited under international law, but their use against civilians and in urban areas is outlawed according to a 1980 weapons convention.

They can cause severe burns and poisoning.

Russia: Heavy Ukrainian casualties all along front

Zelenskyj reported that Russian attacks were also increasing in the north-eastern region of Kharkiv.

Defense Ministry spokesman Igor Konashenkov said the Russian air force had attacked a tractor factory in Kharkiv that housed soldiers and material from the Ukrainian army.

Ukraine is suffering "heavy casualties on all fronts," Konashenkov stressed.

Lukashenko: Kyiv provokes us

Belarusian ruler Alexander Lukashenko said on Saturday: "We are being provoked. About three days ago, maybe more, an attempt was made from Ukraine to attack military targets in Belarus."

However, Belarusian Pantsir air defense systems intercepted all missiles, Lukashenko was quoted as saying by the state news agency Belta on the eve of Belarusian Independence Day.

In a warning apparently aimed at Ukraine and the West, the Belarusian leader said he would respond "immediately" to an enemy attack on his territory.

According to Ukrainian sources, rockets were fired from Belarus at the Ukrainian border area last week.

However, Lukashenko denied on Saturday that his country would intervene in the conflict: "(...) we have no intention of fighting in Ukraine."

Lukashenko, a close ally of Kremlin chief Vladimir Putin, has supported Russia's attack on Ukraine, which began on February 24, by making Belarusian territory available to the Russian army as a base.