It took weeks but police finally figured out what caused the mysterious deaths of these four bears.

*Note: This story was originally published in December 2016.*

Four bears found dead in a Pennsylvania church parking lot likely died from poisoning, officials revealed. The West Wyoming Borough Police and Pennsylvania Game Commission investigated the suspicious deaths, finding no signs of trauma or bullet wounds.

Toxicology tests showed the bears, including a 300-pound mother and three cubs, had ingested leaves and seeds from the English yew plant, which is highly toxic, especially in winter. Other potential toxins, including antifreeze and pesticides, were ruled out. The Game Commission concluded the bears died suddenly from plant toxin poisoning.