Toronto Explosion taken on a Canon HV20 HD Camcorder (toronto-explosion-high-quality-video.mp4)

The fiery mushroom cloud that rose over downtown Toronto last week must have been pretty scary to everyone who saw it. The explosion of a propane storage facility killed two people and forced 12,000 people to evacuate.

The conflagration also made a big impact in the world of Web video: Hundreds of witnesses recorded what they saw and uploaded the scene to YouTube. As of yesterday, a search of "Toronto propane explosion" on YouTube yielded 310 results.

But at least two of those videos -- which happen to be some of site's most popular clips -- aren't what they purport to be.

It just so happens that some of YouTube's biggest stars were in town for the 888 YouTube Gathering. Two of them, sxephil, kevjumba, thought it would be funny to make bogus, "Cloverfield"-style clips of the disaster -- using footage shot by someone who really witnessed it, Toronto resident Saejinoh.

The two videos, which are supposed to appear as if they were made by people who saw the explosions from a hotel balcony, are sort of clever. They've racked up more than 850,000 views in a little more than a week, and they give you a sense of why sxephil and kevjumba are some of YouTube's most-followed video producers. But they also makes us feel at least a little bit squeamish, given the very real impact of the disaster.