LONDON -- If Russia has a legitimate complaint about U.S. forces letting ISIS militants slip through the closing net and escape their territory in Syria, it appears to have undermined its own argument by laying out the charges with bogus "evidence."

Russia's Ministry of Defense on Tuesday alleged in various statements cited by the country's state-run media, and in social media posts, that the U.S. military "provides cover" for ISIS militants on the ground.

The allegations stem from the recent battle for the Syrian town of Boukamal, on the border with Iraq. Last week, Syria's government declared the town liberated from ISIS after a fierce fight for what had been the Sunni extremists' last urban stronghold in the country.

The Russian MoD tweeted on Tuesday a message accusing the U.S. of "direct cooperation and support" for ISIS. The tweet offered four grainy images as "irrefutable evidence" of that alleged support, each purportedly showing an "ISIS automobile convoy" that had been allowed to leave Boukamal by American forces.

"These facts are conclusive evidence that the United States, while imitating an uncompromising fight against international terrorism for the global community, in fact provides cover for Islamic State units," the defense ministry said.

But as Syrian war analyst Elliot Higgins and other online sleuths pointed out on Twitter, at least three of the images appear to be poor attempts to manufacture "evidence"; one is a screengrab from a computer game, and two others are taken from video or images that came out of neighboring Iraq, a year before the Boukamal battle.

"Having done some digging the images appear to have come from a video game called; 'AC-130 Gunship Simulator - Convoy engagement,' made by a company called; byte conveyor studios," said Higgins.

His own evidence was more convincing; footage from the game posted on YouTube clearly shows an uncropped version of the same image tweeted by the Russian ministry. The Russian tweet failed even to crop out completely the English language text at the top of the computer game screen, which identifies it as "DEVELOPMENT FOOTAGE."

A screengrab from a

The tweet with the fraudulent images was deleted from the Russian MoD's feed later Tuesday, but not before drawing an onslaught of abuse and ridicule from other users on the social network.

Higgins, whose Bellingcat organization spends thousands of man-hours pouring over open-source information to prove and disprove claims from the Syrian battlefield, said in a subsequent post that the use of the bogus images proves Russia's claims about Syria cannot be taken seriously.

Prior to Russia's allegations on Tuesday, there had been no solid claims that the U.S. military was letting ISIS fighters -- there were an estimated 2,500 to 3,500 ISIS militants around Boukamal, reportedly including some senior figures -- escape. However, local opposition groups and monitors said militants did flee the battle to the north, taking refuge in a handful of towns along the east and west banks of the Euphrates River between al-Mayadeen and Boukamal.

And while is no evidence to support Russia's claim that the U.S. is directly supporting ISIS on the battlefield, if Moscow wanted to portray the U.S. as somehow giving some of the extremists a pass, it could have just cited BBC News.

Read more at CBSNews.com.