If you have seen footage of Russian vehicles recently, you may have noticed the letter 'Z' painted on the side — a symbol which even has experts confused.
In several videos and photos posted on social media, Russian tanks and trucks are seen to be emblazoned with a white 'Z' and it appears to have caught the attention of a few people, including intelligence experts.
"Many people ask us about this 'Zorro squad', but I don’t know why they draw this giant Z on vehicles," the head of Conflict Intelligence Team, Ruslan Leviev, said on Twitter.
The Conflict Intelligence Team is an "independent Russian investigative organisation", according to Al Jazeera.
"Some believe that this is a sign for their own aircraft, so that their own would not be bombed. But we see a lot of movement of vehicles every day and this Z is very rare," Leviev said.
However Leviev questioned if it was a measure to ensure Russians didn't bomb their own, why wasn't the symbol on all their equipment.
The director of training and research at Bellingcat – an independent collective of researchers, investigators and citizen journalists, Aric Toler, retweeted Leviev and said the 'Z' branding had only just started to appear.
He added Leviev had been monitoring this kind of thing for eight years.
"So, assume the worst, I guess/fear," he added.
Analyst Oliver Alexander offered up another theory, saying the 'Z' could just be for logistics.
"The 'Z's could be as simple as NCOs (non-commissioned officers) telling vehicle crews to mark their vehicles after completed ready checks," he wrote on Twitter.
"This is why you have no system or standardisation at all. The truck with the massive Z is 'that guy' and also the reason why there was a smaller Z painted on the door."
In another series of earlier tweets, he said: "With all other distinguishable unit markers painted over the Z we are seeing were most probably to identify which vehicles are heading for this specific attack corridor into Ukraine during mobilisation from camps.
"With hundred of vehicles at some of the forward camps we have seen, it would have been important to ID which specific vehicles are moving out and where too. With IDs painted over this would be a logistical nightmare. The symbol makes this possible."
Russian troops 'poised to strike', US says
The White House has said the US president's national security team has advised him they believe Russia could attack Ukraine "at any time".
Foreign ministers from the G7 group have said they have not seen any evidence Russia is reducing its military activity near Ukraine's border.
Washington has gone as far as accusing Russian troops massed near the border of advancing and being "poised to strike".
Foreign ministers from the G7 group of rich nations said they had seen no evidence Russia is reducing its military activity in the area and remained "gravely concerned" about the situation.
US Defense Secretary Lloyd Austin said Russian forces were beginning to "uncoil and move closer" to the border.
"We hope he (Vladimir Putin) steps back from the brink of conflict," Austin told a news conference in Lithuania, saying an invasion of Ukraine was not inevitable.
Russia has said Western warnings about the invasion of Ukraine are hysterical and dangerous and Moscow says the military is pulling back.
Russia ordered the military build-up while demanding NATO prevent Ukraine from ever joining the alliance.
The world against Russia
Scott Morrison has warned Russia the world will be moving together to counteract any violence it inflicts on Ukraine.
Washington believes Russian troops massed near Ukraine's border are advancing and are "poised to strike".
"It is unacceptable because it is unwarranted, it's unprovoked in terms of the threats of terrible violence that Russia is imposing on Ukraine," the prime minister told reporters in Melbourne on Sunday.
He said while there has never been any contemplation of Australian troops being deployed to Eastern Europe, the government has been working with its allies to directly support Ukraine, whether it be in cyberspace or things of that nature.
"The world will be moving together to seek to counteract what would be a terrible act of violence," Mr Morrison said.
"Should they follow through on their acts of violence against Ukraine, we will follow through with sanctions together and in partnership with all of our other allies and partners."
He said Foreign Minister Marise Payne will be meeting with her Ukrainian counterpart on Monday.
Opposition Leader Anthony Albanese reiterated his call for Russia to "back off".
"There is no place for the intimidation and threats that we've seen from Russia against a sovereign government, which should be respected," Mr Albanese told reporters in Darwin.
Defence Minister Peter Dutton said while he was hoping for an "11th hour miracle", it was very hard to see how that would be the case and expects there would be an incursion into the Ukraine.
"It's regrettable, but I think that's the action that Putin is intent on," Mr Dutton told Sky News' Sunday Agenda program.
He said the alliance now between China and Russia was deeply concerning.
With Reuters and AAP
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