Customs inspectors at the Calexico border crossing grew suspicious about a woman in a van, pulled her over and found 416 pounds of marijuana and 43 pounds of cocaine hidden in the vehicle, authorities said. Susana Robles Sanchez, 35, a U.S. citizen living in El Centro, was arrested on suspicion of attempting to import a controlled substance, customs officials said. If convicted, she could face a prison sentence of 10 years to life and a fine of up to $4 million. Customs inspectors would say only that agents noted that “the circumstances were similar to established smuggling profiles” when they halted the van. After a dog trained to sniff out narcotics gave strong indications that drugs were in the van, agents searched the vehicle and found a false compartment under the floor, authorities said.