Murdered Russian oppositioner Boris Nemtsov was working on a report allegedly containing evidence of Russia's direct involvement in Ukraine's unrest, according to Nemtsov's fellow colleagues.

Ilya Yashin, an activist who had close ties to Nemtsov, told Ekho Moskvy radio he had spoken to Nemtsov two days before his killing on Thursday evening.

In his words, there is no doubt his murder was of a "political" nature.

Various media outlets, including German weekly Der Spiegel, have focused their attention on the fact that Nemtsov was among President Putin's staunchest critic. Der Spiegel's story in particular is titled: "Attackers Shoot Putic Critic Nemtsov Dead", hinting political motives might be involved.

"With the murder of Boris Nemtsov a new are beginns for Russian oppositioners, an age of fear," the magazine notes.

Others recall his comments of mid-February that he feared for his life as Putin might "kill" him.

In his words for Sobesednik, a Russian media outlet, of February 10, he said the President might choose to punish him for some of his comments.

Stanislav Belkovsky, a political analyst once affiliated with prominent Russian businessmen and known for his insight on Vladimir Putin's policies and personality, has ruled out that the Russian President could be anyhow interested in Nemtsov's death.

But he admitted "the atmosphere of hatred to those with alternative thinking created over the past year since Crimea's annexation [sic] could have played its part," Belkovsky added.

Ошибся на месяц... pic.twitter.com/HIN2JjopI8

— Станислав Белковский (@st_belkovsky) February 28, 2015

Belkovsky later reminded of his recent forecast that something important would happen in Russia by January, 2015. "I was wrong with a month," he announced.

More to follow.