A Russian attack on a Ukrainian military training base on Sunday has killed at least 35 people and injured 57 others, officials confirmed. 

Officials provided an update on the death toll around 11am this morning.

More than 30 cruise missiles were fired at the Yaroviv military range, the regional administration confirmed. 

The airstrike took the war closer to the border with Poland after a senior Russian diplomat warned that Moscow considers foreign shipments of military equipment to Ukraine “legitimate targets”.

The range is located north-west of Lviv and is around 22 miles from the border of Poland. 

Since 2015, the US has regularly sent instructors to the military range, also known as the Yaroviv International Peacekeeping and Security Centre, to train Ukraine’s military.

In an intelligence update on the Russian invasion, the Ministry of Defence confirmed that invading troops are also attempting to envelop Ukrainian forces in the east of the country. 

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Russian forces are advancing from Kharkiv in the north and Mariupol in the south, the report confirmed. 

“Russian forces advancing from Crimea are attempting to circumvent Mykolaiv as they look to drive west towards Odesa," it added.

“Russia is paying a high price for each advance as the Ukrainian Armed Forces continues to offer staunch resistance across the country.”

On Saturday, Russia bombarded cities across Ukraine, pounding Mariupol in the south, shelling the outskirts of the capital, Kyiv, and thwarting the efforts of people trying to flee the violence.

Talks aimed at reaching a ceasefire again failed on Saturday, with residents of Mariupol forced to endure unceasing attacks interrupting efforts to bring food, water and medicine in the city. 

More than 1,500 people have died in the city during the Russian siege, according to the mayor’s office, and the shelling has even interrupted efforts to bury the dead in mass graves.

Ukrainian President Volodymyr Zelensky accused Russia of trying to break his country apart, as well as starting “a new stage of terror” with the alleged detention of a mayor from a city west of Mariupol.

“Ukraine will stand this test. We need time and strength to break the war machine that has come to our land,” he said during his nightly address to the nation on Saturday.

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Russian soldiers pillaged a humanitarian convoy that was trying to reach Mariupol and blocked another, a Ukrainian official said.

Ukraine’s military said Russian forces captured Mariupol’s eastern outskirts, tightening their siege of the strategic port. Taking Mariupol and other ports on the Azov Sea could allow Russia to establish a land corridor to Crimea, which it seized from Ukraine in 2014.

In Irpin, a suburb about 12 miles (20km) north-west of central Kyiv, bodies lay out in the open in streets and in a park.

“When I woke up in the morning, everything was covered in smoke, everything was dark. We don’t know who is shooting and where,” resident Serhy Protsenko said as he walked through his neighbourhood. Explosions sounded in the distance. “We don’t have any radio or information.”

Mr Zelensky encouraged his people to keep up their resistance.

“We do not have the right to let up our defence, no matter how difficult it may be,” he said.

Later on Saturday, he reported that 1,300 Ukrainian soldiers had died since the Russian invasion began on February 24.