A four-month crackdown on international crimes, such as illegal entries and drug trafficking, has resulted in the detention of 1,089 people, the Korean National Police Agency said Wednesday.

The crackdown, conducted from March 4 to July 12, mainly targeted illegal employment of foreign workers, fake visa issuance, drug manufacturing and smuggling, and voice phishing, the agency said, noting 237 of the 1,089 detainees were formally placed under arrest.

The crackdown busted 557 cases, and illegal entries and departures accounted for 352, or 63.2 percent, followed by drug crimes (186 cases), crimes by international criminal rings (17 cases) and sex crimes (two cases), it said.

Foreigners accounted for 794 of the 1,089 detainees, with the rest being South Koreans. Asians accounted for 91.4 percent of the foreign detainees.

In case of illegal entries and departures, 699 people were detained, and 54 of them were arrested. In one case, the Seoul police last month detained 111 brokers and employers of Thai women who had illegally worked at a massage parlor in Guri, east of Seoul, after arriving here on a tourist visa.

The KNPA said 330 people were detained for drug crimes, and 140 of them were placed under arrest. Illegal drugs were mostly smuggled via international mail and parcel. In March, the police detained three Chinese and Taiwanese nationals for mass-producing methamphetamine at a hotel in downtown Seoul and smuggling ecstasy, while 41 people from China and Kazakhstan were detained for distributing illegal drugs, like methamphetamine and Spice, in Incheon.

Police have also detained 57 members of international criminal rings and arrested 43 of them. The Seoul police detained 28 members of a voice phishing ring based in Qingdao, China, in June, while police in Ulsan arrested seven Russian gangsters in May on charges of committing abduction, robbery and other crimes.

"The police will continue to crack down on crimes of international criminal rings and violent crimes by foreigners to further enhance public security," a KNPA official said. (Yonhap)