XI'AN -- Police in Northwest China's Shaanxi province seized 7.2 kilograms of drugs hidden in steel gears, local police said Friday.

The suspects, surnamed Li and Chen, used five customized steel gears 28 centimeters in diameter and 5.5 centimeters thick for holding methamphetamine, according to police in Ankang city.

"The hollow gears are packed with drugs in small plastic bags and look no different than normal gears," said a policeman handling the case. "The drugs in it can even escape X ray detection."

The case is still under investigation.