Belgian police have seized 550 kilograms (1,200 pounds) of illegal anabolic steroids in the biggest single seizure of the drug in Western Europe, officials said.

Side effects of anabolic steroids

Acne Facial hair in women Breast development in men Shrunken testicles Infertility Depression Insomnia Mood swings

The haul was discovered in three searches near the border with the Netherlands, which took place on Friday and Tuesday.

The drugs, worth $136.5m (£87.5m), were destined to be sold in six different countries, probably mainly in Britain, a police spokesman said.

Two men and a woman were detained during the raids.

Future raids

Further searches were being planned, a police spokeswoman said.

The spokeswoman said in Belgium the steroids, found in capsule and pill form, were "just as illegal as cocaine and heroin".

Anabolic steroids are used illegally by some bodybuilders and athletes to enhance performance.

Medical experts are concerned their use is spreading among amateur fitness enthusiasts. They link the use of steroids to depression and say the drug can lead to liver and kidney diseases.