Since late March, a pack of dogs has been roaming the countryside of Washington state, killing farm animals and leaving residents terrified. The killer canines have been spotted twice during the day, and once on camera, but their nocturnal hunting habits have kept authorities at bay. Here, a brief guide to the mayhem:

Exactly how much damage have these canines caused?
The pack has killed at least 100 animals over the last few months, including $3,500 worth of sheep, goats and chickens. They even took down a 350-pound llama, suggesting that they could easily take down a human. Authorities can't predict where the pack will strike next, leaving residents wondering if their families and farmlands are safe. "What is going to happen if they come across a small child?" asks Lavonne Webb, a local undersheriff, as quoted by the Associated Press.

How many dogs are we talking about here?
Authorities speculate the pack is made up of four or five large canines of various breeds. Only one snapshot of a packmember has been captured, showing a white dog snarling outside a fenced-in area and looking, as one resident put it, "bloodthirsty."

Where did the pack come from?
The dogs could be wild or feral, but they could also be going home to owners during the day and returning to the pack at night. While volunteers and officers continue their search, the dogs are playing a mean game of hide and seek, keeping quiet during the day and hunting only after dark. "The dogs, it would seem, are in complete control," says Curtis Cartier at Seattle Weekly.

So… are these dogs just really hungry?
It actually looks like they're "killing for kicks," rather than for food, says Larry McShane at the New York Daily News. Karen Overall, a specialist in veterinary behavioral medicine, disagrees. "I'm seeing no evidence this has anything to do with sport," Overall told TIME. They could be killing because of an immediate threat, or even taking food to an injured pack member. "I don't think these animals are killing for the sake of killing," she says.

Sources: TIME, Associated Press, Seattle Weekly, KREM, Daily News