It appears it is raining poop in Canada. This strange phenomenon has been happening for over a month now and the officials did not offer any solid explanations yet.

Everything started on May 9th in British Columbia. A woman was in the car with her son and was stopped at a red light. At some point, it started raining, but it was no regular rain. When the two looked up through the car’s open sunroof, they were more than surprised to see that they were “inundated” not with rainwater, but with liquid and wet feces.

“I started crying (and) I’m like: ‘I’m covered in poo,’ ” Susan Allan told in an interview. “It was just falling from the sky. You could feel the drops hitting you. When I looked up there was nothing above but a plane flying.”

Three days after this happened, another man living in the same town was shocked to find his car splattered in something that appeared to be poop. The most recent event presents a woman located at more than 3,000 km (1,864 miles) away. While she was enjoying her afternoon on the deck, sometime around 4 pm, she noticed some “black liquid” falling from the skies and splattering not only her deck but also the windows and railing.

“It was like somebody’s septic tank burst,” Linda Smith said in an interview she gave to CBC news. “It was really bad.”

There have been 18 different reported cases of poop falling from the sky throughout entire Canada, but the truth behind these unfortunate events is not yet completely clarified.

One possible theory involves “blue ice”. It is known that airplane staff is not allowed to empty toilets while the plane is in the sky, as this could have unpleasant consequences and could be categorized as health violation, but the truth is that accidents do happen. It may happen that sometimes human waste dyed blue due to the use of chemical deodorizer in lavatories seeps outside of the plane.

“If this happens, the liquid seeping from valves freezes and adheres to the outside of the aircraft when the aircraft is flying at high altitudes,” Transport Canada, the government department that deals with federal transportation and that is responsible for investigating these incidents told in an interview they gave to CBC.

“As the aircraft starts its [descent] and the atmosphere gets warmer, the ice will start to melt and pieces will detach themselves from the aircraft. These pieces of ice will either melt or remain in their solid state before hitting the ground,” they added.

But even so, no official explanation has been provided yet to the public. After talking to various aviation crews and investigating local radar and reviewing reports, it appears that Transport Canada has reached the conclusion that whatever is falling from the sky is not poop, as it does not “meet the description of blue ice”.