Given the previous suggestion by Russian authorities that Nemtsov's killing might have been perpetrated by Ukrainian agents, and speculation that it might have been connected to damning evidence he claimed to possess of direct Russian involvement in the Ukrainian conflict, we'll post this breaking story here:

Two 'Caucasus' Men Detained 'On Suspicion Of Committing' Nemtsov Killing

Good pushback by Alexander Motyl, via Newsweek, against this particular narrative, titled Putin’s Invasion Of Ukraine: Don’t Blame The West:

Much Western thinking about the causes of the Russo-Ukrainian War is rooted in a myth. It posits that the West—or, more specifically, NATO—attempted to wrest Ukraine from Russia’s sphere of influence, thereby forcing Vladimir Putin to defend Russia’s legitimate strategic interests by going to war with Ukraine.

The logic is impeccable. The only problem is that there isn’t a shred of truth to this claim.

Later:

The fact is that Putin unleashed war against Ukraine for the same reasons that Saddam Hussein unleashed war against revolutionary Iran in 1980: to prevent revolutionary contagion, to punish the revolutionaries and to take advantage of their weakness to make territorial gains.

Today's military situation map via Ukrainian authorities:

They have misled before, however.

This quote isn't unequivocal. Perhaps lost in translation, but "last day" need not mean "achieved."

AFP's report:

Pro-Russian rebels in eastern Ukraine claimed Saturday to have completed their withdrawal of heavy weapons, in line with a February ceasefire deal.

"Today is the last day of the weapons withdrawal," Edouard Bassourine, one of the rebel leaders told reporters in the town of Snizhne, where the separatists presented 120mm mortars removed from the frontline.