The head of the Wagner mercenary group chief, Yevgeny Prigozhin, has launched a scathing new attack on Vladimir Putin‘s invasion strategy, claiming that Russia could face a revolution similar to 1917 and lose the war in Ukraine unless changes are made by Kremlin leadership.

The Wagner chief, who was once a close ally of the Russian president, said Moscow’s invasion has seen Ukraine amass “one of the world’s strongest armies” with Western support.

“We made Ukraine a nation, known to everyone around the globe,” he said in an interview with prominent Russian pro-war blogger Konstantin Dolgov. “They are like Greeks at their peak, or Romans.”

Mr Prigozhin said Ukraine now has more tanks and more troops than it did at the start of the war. “We militarised it up to the brim,” he said.

Russia‘s Federal Security Service (FSB) said on Thursday it had detained two Ukrainian saboteurs who were plotting to blow up the power pylons of nuclear power stations in Russia, the RIA Novosti news agency reported.

One of Ukraine’s special military or intelligence units was likely behind the dramatic drone attack on the Kremlin seen earlier this month, assessments by US spy agencies show.

The attack, which appears to be part of a series of covert operations, made officials in Washington uncomfortable, reported the New York Times.

The US assessment was based on intercepted Russian and Ukrainian communications, the paper said.

Officials in the US intercepted Ukrainian conversations in which officials said they believed their country was responsible for the attack and also intercepted Russian communications which indicated it was not some sort of false-flag operation by Russia, the report added.

It added that the US does not believe Ukrainian president Volodymyr Zelensky signs off all covert operations and the extent of his awareness on such operations in advance remains unclear, the officials said.

While the Kremlin squarely blamed Ukraine for the attack and called it an attempt to assassinate Vladimir Putin, it also accused the US of being behind the incident.

Mr Zelensky swiftly denied Ukraine’s involvement, saying that the war-hit nation only carries out defensive operations on its own soil, and Washington dismissed Russia’s allegations as ridiculous.

Russian air defences managed to down six drones overnight in different areas of the peninsular region, Moscow-backed head of Crimea’s administration said today.

No casualties have been seen so far, Russia-installed governor Sergei Aksyonov said on Telegram.

Britain’s Ministry of Defence (MoD) says pro-Russian actors risked a maritime safety incident by tricking vessel tracking data to create a 65km-long pro-war Z symbol at sea.

The “spoofing” of vessels’ Automatic Identification System (AIS) data was likely done to boost Russian morale, the MoD said.

“Analysis by Geollect indicates that since 14 May 2023, commercial vessels’ Automatic Identification System (AIS) data has been remotely spoofed to create the impression of a 65km long Russian pro-war Z symbol on the Black Sea, visible on open source tracking software,” the ministry said in its latest intelligence update.

It added that the AIS is used to track vessels, including to ensure their safety, and the tracks “making up the image suggested vessel speeds of up to 102 knots (188 km/h), further suggesting they were fake”.

“Pro-Russian actors likely conducted the spoofing as an information operation, potentially in an attempt to bolster Russian morale ahead of an anticipated Ukrainian counter offensive,” the ministry said today.

It added that the spoofing of AIS increases the risk of maritime accidents.

“Despite Russian virtual information operations in the Black Sea, its physical navy remains vulnerable: the Ivan Khurs intelligence gathering vessel was likely attacked on 24 May 2023,” it said.

Wagner has lost one in five convicts recruited to fight in Ukraine, the mercenary group’s chief Yevgeny Prigozhin said.

“I took 50,000 prisoners of which around 20 per cent were killed,” Wagner chief Prigozhin said in a video interview on late Tuesday, adding that around 10,000 of Russian prisoners recruited to fight in the continuing war have been killed on the battlefield.

A similar percentage were killed among those who had signed a contract with Wagner but did not share an exact number of casualties.

Ukrainian forces are improving their defence faster than Russian can change its terror tactics in the war, Volodymyr Zelensky said after a meeting with his commander-in-chief and the head of Ukraine’s main intelligence directorate.

“We know how to respond. In particular, this applies to the missile threat and the constant terror of kamikaze drones. Now Russia is increasingly resorting to so-called combined strikes – different types of missiles, different types of drones,” he said in his nightly address.

He added: “I am grateful to our Air Force, to all our defenders of the sky, to our intelligence for improving our defence faster than Russia can change its terror tactics.

“If we take, for example, just one weapon of Russian terror, the Iranian Shaheds, our soldiers have shot down almost 900 of these drones to date. In total, about 1160 Shaheds have been used against Ukraine. We shoot down most of them,” Mr Zelensky said.

Ukraine has shot down all Russian aerial targets during an early morning attack on Kyiv, the capital city’s military administration head Serhii Popko said.

Russian forces used drones in their 12th mass attack this month against Kyiv and the military offensive lasted over three hours, Mr Popko said, adding that “all potential strikes on Kyiv have been prevented”.

South Korea has dispatched hundreds of thousands of its artillery rounds and the ammunition package is on its way to Ukraine via the United States, according to a new report.

Seoul had managed a “confidential arrangement” with Washington to transfer the artillery shells to the US to be delivered to Ukraine, reported the Wall Street Journal, citing a source.

This comes after Washington asked its Asian ally last year for artillery support.

Jeon Ha-kyu, spokesperson at South Korea’s defence ministry, confirmed that the country had been in talks with the Pentagon on ammunition exports but that there were “inaccurate parts” in the WSJ report, declining to give details.

“There have been various discussions and requests, and our government will take appropriate measures while comprehensively reviewing the war and humanitarian situation in Ukraine,” Mr Jeon told a briefing.

Up until very recently, South Korea had ruled out sending military aid to Ukraine due to its business relations with Russia in addition to Moscow’s influence over North Korea which has been targeting it in the peninsular region.

The US ally and major producer of artillery ammunition had refused the requests despite the mounting pressure from Washington and Europe to supply weapons.

But in April, president Yoon Suk Yeol signalled the prospect of a change, saying it might be difficult for Seoul to adhere to only providing humanitarian and financial support if Ukraine faced a large-scale civilian attack or a “situation the international community cannot condone.”

Russian officials have rejected reports of a heavy fire at its Ministry of Defence building in central Moscow after visuals showed thick smoke billowing out of its balcony.

“A fire broke out on a balcony at the ministry of defence building on Frunzenskaya Naberezhnaya,” reported TASS news agency, initially quoting an emergency services source as saying.

Emergency services were also reported to be working at the scene.

However, local officials later said a fire had not been detected at the building, TASS reported.

“The presence of a fire has not been confirmed, as no fire was detected by the fire brigade upon arrival. Neither is there any information about victims,” TASS quoted Moscow’s Ministry of Emergency Situations as saying.

Several people took to social media and shared visuals of smoke around the defence ministry building adding that a “toxic smell of burning plastic” was also detected.