RIO DE JANEIRO, Jan. 19 (Xinhua) -- Brazilian police Monday seized 903 kg of cocaine and arrested at least 13 people in an operation aimed at breaking up an international drug trafficking ring operating in the country.

    Lawyers as well as businessmen from sectors of construction, tourism and vehicle trade were among the arrested in the raid dubbed as Operation Alpha. Their identities, however, were not revealed by the federal police.

    Handguns, machine guns, several types of ammunition, and some drug processing equipments were confiscated along with the drugs.

    Investigation for Operation Alpha started in April 2007, when a federal police found dealers from Mato Grosso state negotiating a shipment of drugs with buyers from the town of Sao Jose do Rio Preto, Sao Paulo state.

    The federal police had reported four different groups in the drug smuggling ring, with one of them owning a construction company in Cuverlandia, Mato Grosso state and having projects in Bolivia. The group had been using the company's vehicles to transport cocaine from Bolivia to Brazil.

    Another group airlifted drugs from Bolivia's eastern Santa Cruz de la Sierra and the remaining two traded cocaine in Brazil's Sao Paulo.

    According to the federal police, Operation Alpha was launched in six Brazilian states, during which a total of 85 temporary prison warrants and 89 search warrants were issued.