Activists in fire truck try spray painting UK treasury building to protest climate change. It doesn't go so well. (12 Pics)

You know the old saying: "Let the buyer beware" — i.e., caveat emptor.

Apparently some climate activists never took Latin.

You see, the good folks at Extinction Rebellion had it in mind to spray paint the British finance ministry building red Thursday to drum up attention concerning what they said was the government's failure to stave off climate change, Reuters reported.

So they drove up to the British Treasury in a fire engine, grabbed a hose, and took aim.

Getcha popcorn ready

Keep in mind the outlet said Extinction Rebellion purchased the fire truck on eBay.

For a few seconds things appear to go as planned. The hose seems in fine working condition as the red paint starts hitting the building:

Then — boom:

A malfunction, putting it gently, apparently befalls the group as the hose appears to explode in the faces of the gents aiming it at the treasury.

And soon the hose is spraying red paint everywhere — except upon the building's outside wall:

A couple of intrepid folks try to get things under control — but to no avail:

The hose of the eBay-purchased fire engine is just too powerful — and soon the street is flooded with red paint:

Oh, and did we fail to mention there's video?

Yes, indeed, there is. Check it out:

What happened afterward?

Reuters said activists stood atop the fire engine sporting a banner which read, “Stop funding climate death."

One activist was seen spray painting the same slogan on the walls of the building — albeit employing a much more controllable method:

Extinction Rebellion added to the outlet that they sprayed 1,800 liters of fake blood at the Treasury — although "at" may be stretching it a tad, prepositionally speaking.

“The Treasury has been frustrating efforts by other government departments to take action against climate change because it cares only about economic growth," one activist who called himself Ben told Reuters. “It doesn't see that eternal economic growth leads to climate death. The red symbolizes the people dying now in the global south and also the people who are going to start dying from climate change all around the world if we do nothing."

Police told the outlet they arrested four people on suspicion of criminal damage and that some roads had been closed. Reuters also said police weren't sure what to do with the fire engine as the driver removed the keys.

It wasn't clear if Extinction Rebellion will ask eBay for a refund.