Grower Denis Contry prepares medicinal oil with marijuana extract at Ganja Farms marijuana store in Bogota, Colombia. (Photo: REUTERS/John Vizcaino)

SAN DIEGO: On the afternoon of May 5, college student John Nothdurft was watching TV at his suburban San Diego home when a series of explosions shook the house. Around the corner, on Sunny Meadow Street, flames billowed from a neighbour's garage.