The discovery stunned even veteran law enforcement officials used to seeing all kinds of contraband smuggled into prisons.

US Customs officials say drug-smuggling techniques range from old-school tricks such as packing bricks of cocaine into false-bottom suitcases to sophisticated methods of disguising drugs as freeze-dried coffee or black-eyed peas.

Experts say even as surveillance equipment, airport scanning technology and cargo X-rays modernize, drug-smuggling techniques are keeping pace.

Traffickers also use a variety of ways to transport drugs, such as putting them in miniature submarines or using an old-fashioned catapult to hurl them over the United States-Mexico border.