The final report of prominent Russian opposition politician and Kremlin critic Boris Nemtsov, who was gunned down on the streets of Moscow in February, was published Tuesday by his former colleagues. It promises to be explosive.

The 64-page report, titled simply "Putin. War," contains all of the evidence collected by Nemtsov in the final months of his life as he looked into Russia's role in the ongoing crisis in Ukraine that has so far cost over 6,000 lives.

The various documents, pictures, and statements that form the core of the report have been painstakingly collected and collated by fellow opposition activists since Nemtsov was shot dead in a case that many suspect was politically motivated.

Ilya Yashin, a Russian activist and liberal politician who worked closely with Nemtsov, presented the report to journalists and activists at the headquarters of the political party he cofounded with Nemtsov, RPR Parnas. In his remarks, he said "preparing the report on Russian losses in Ukraine was one of the reasons behind his assassination."

The report alleges that Russia played an active part in the war in Ukraine despite official denials from the Kremlin that its troops were involved. It alleges that Russians paid a heavy cost both in terms of hundreds of troops' lives and billions of dollars of taxpayer money.

A Russian T-72 tank said to be captured from separatists by Ukrainian government forces. http://smitsmitty.livejournal.com

It ties together interviews with soldiers who say they fought on the frontlines and disguised Russian vehicles so they wouldn't be identified in Ukraine, alongside pictures of Russian troops and heavy weapons allegedly spotted in the country and reports of widespread hiring of Russian mercenaries to fight against Ukrainian government forces.

Overall, the authors estimate that the war in Ukraine cost Russia about $2.5 billion in mercenary fees and refugee assistance alone.

It also alleges that the annexation of Crimea, which led to international sanctions against Russia that helped send it into a deep recession, was orchestrated by the Kremlin to prop up Vladimir Putin's flagging popularity ratings.

Putin's press secretary, Dmitry Peskov, told reporters on Tuesday that he hadn't yet read the report and was unsure whether he would. He said: "I'm not familiar with that report, so can not say anything."

The report can be read in full online (in Russian). Here is the introduction in full:

The idea behind this report belongs to Boris Nemtsov. One day he went to the party headquarters and loudly said: "I have come up with what to do. We must write a report, "Putin. War," published in huge circulation and given the streets. Let us tell people how Putin unleashed the war ...

From the beginning of 2015 Boris began to collect material for the report. He has worked with open source, finding people who could share information. Nemtsov believed that attempting to stop the war is the real patriotism. The war with Ukraine is a cynical and cowardly crime for which our country is paying the price in the blood of its citizens, the economic crisis and international isolation.

No one in Russia needed this war, except for Putin and his entourage. Boris did not have time to write the report. On February 27, he was killed on the Greater Moscow River bridge, next to the Kremlin walls. To complete the project it took his colleagues, friends and people who considered this important work. The report is based on materials that Boris had prepared. The content of handwritten notes, documents — everything that he had left — was used in the preparation of the text.

Our task is to tell the truth about the Kremlin's interference in Ukrainian politics, which led to a war between the two nations. It led to a war, which must be stopped immediately.