The Fair Trade Commission on Wednesday searched the headquarters of an agrochemical firm in Chiyoda Ward, Tokyo, and other company offices on suspicion that the firm has been illegally fixing the price of a popular pesticide.

The FTC raided more than 20 locations, including the headquarters and five offices of Nissan Chemical Industries Ltd. following an allegation that the company violated the Antimonopoly Law by threatening to stop providing retail stores with a product called Roundup Hi-Load if they refused to set a certain sales price for the product.

Roundup is a popular pesticide developed by U.S. chemical company Monsanto Co.

Nissan Chemical started distributing the product in 2002 after buying the pesticide business of Monsanto Japan Ltd., which had been distributing the product since July 2000.

According to sources, Nissan Chemical had been selling Roundup to retailers nationwide but allegedly used the product's popularity as leverage to demand that they not discount prices. Roundup is popular for its wide range of uses -- it can be used on anything from veranda gardens to farmland. The product retails for about 1,500 yen for a 500-ml container.

Nissan's alleged pressure may violate the Antimonopoly Law, which bans unfair business practices, the sources said.

According to the firm's Web site, Nissan Chemical, the first chemical fertilizer manufacturer in Japan, was established in 1887 and is capitalized at 18.9 billion yen.