Hundreds of police and health inspectors raided 55 drugstores in the border city of Tijuana and found some of them illegally selling drugs ranging from veterinary medicines to powerful tranquilizers and "date-rape" drugs.

Dozens of shipments of drugs were seized and three of the pharmacies were closed, the Health Department said Friday in a press statement. The stores' clients includes American customers attracted by lower prices or looser prescription requirements.

Irregularities were detected at 26 of the 55 drug stores, including the sale of tranquilizers and psychotropic drugs like Valium and Halcion, and the "date rape" drug flunitrazepam, known by the trade name Rohypnol.

Only specially-licensed drug stores are allowed to sell those drugs in Mexico. Other problems detected included bulk medicine sales and inadequate sanitary controls.

Police also seized lots of three veterinary drugs for use in animals, but which were displayed in the stores, apparently for human consumption.

"The majority of these drugs arrived illegally in Mexico from the United States, Guatemala, Panama, India, China" and other countries, according to the press statement.