Girkin was quoted as saying that the victims of MH17 "may have already been dead before the plane took off from Amsterdam on Thursday."
MH17 was flying from Amsterdam to Kuala Lumpur with 298 people on board when it went down in Donetsk, eastern Ukraine, near the Russian border, on Thursday night.
It is believed that MH17 was hit by a surface-to-air missile fired by the separatists.
"Of course, they died mid-air because you shot them with a freakin missile, you moron!" Chandran Raman Kutty commented in The Star Online's Facebook.
Other netizens also gave Girkin a tongue-lashing. Ariana Urike called him an "idiot" in her posting, saying, "he saw fatal injuries from the missile hit? The effects of instant decompression at 30.000 ft? The man is an idiot!"
Similar views were shared by Mala Richards who said, "The lack of intellect expressed by rebels/eye-witness rebels exemplifies exactly how weapons placed in their trigger-happy hands can bring down an innocent passenger plane."
Anger also came from Mer So, who said "Garbage! Rubbish! Nonsense! Trying to cheat babies!"
Sasun Vartanyan wrote: "What an idiot...a murderous IDIOT..." while Shalene Kuek said, "He is such a cruel idiot" while JackieMk Lau said, "He still dare to say such a thing, biggest murderer on the world!"
Some, like Vijaya Raghavan Nair said that Girkin should meet the same fate as the passengers, saying; "Lets blow you up and see if you are fresh smelling and glowing with good circulation!"
Other netizens like Danny Ting slammed Girkin, holding him responsible for ordering the death of all on board MH17 saying; "This guy is a murderer.....I would like to chop off his head if i was given the chance!"
Glassy Mulder Bhandal added, "Igor Girkin you should be hanged to death" and Gurcharan Singh said, "Wanted dead or alive should apply to you murdering low life unnamed fathered moron."
Meanwhile netizens like Lim Pei Yiing questioned the respect shown to the victims of the crash.
"Ya? What do you think this is? Going to market to buy meat and fish? This talk about bodies being fresh or not is pure idiocy and disrespect to the victims," said Lim.
Andrew Chung Kwong Ching added: "Weren't fresh, what do you expect after an explosion. How fresh is your definition of fresh should be?"