Authorities in Mexico are investigating the deaths of four people reportedly killed by a pack of dogs in a park.

BBC: Mexican pack of stray dogs 'kills four' in park

Or a machine that can sniff out explosives with greater accuracy than a pack of police dogs.

FORBES: The Secrets of Scent

Reports say a pack of stray dogs entered the zoo on Saturday night and attacked the blackbucks.

BBC: India: Probe into blackbuck killings at Kanpur zoo

The only thing there was a pack of hot dogs.

CNN: What are you thankful for?

But the only direct challenge we encountered on the rutted track came from a pack of 12 wild dogs that briefly blocked our path, and then lazily chased our small convoy for a few hundred metres.

BBC: Condition of Somali refugees in Kenya worsening

The series, which follows Mr. Millan as he works at rehabilitating aggressive dogs, showcases his philosophy that healthy, balanced dogs require strong "pack leadership" from their owners in the form of exercise, discipline and affection.

WSJ: Me & My Brand: Lively Entrepreneurs Ring Up Sales