Police either made arrests in or turned over to prosecutors 79 cases of alleged human-trafficking involving foreign women forced into the sex industry or other forms of exploitation last year.

The National Police Agency said Thursday that the latest figure, up 28 from the previous year, is the highest since the agency began using a more comprehensive format to compile statistics on human-trafficking in 2001.

The 79 cases netted 58 trafficking suspects, up 17 from the previous year, and 23 brokers, nearly three times as many as the previous year.

Seventy-seven foreign women were victims of human-trafficking in the cases, down six. The victims were found working in such places as hostess bars and strip joints.

By country, the largest group of women came from Thailand, at 48, followed by the Philippines, Colombia and Taiwan, the report says.

In one case, a Thai teen was forced into the sex trade to pay off her 5 million yen debt.

The cases are believed to be just the tip of the iceberg. Human rights groups and researchers estimate thousands of women, mostly from poor parts of Asia, are trafficked into Japan every year and forced to work in the sex trade.

Japan came under international pressure last year to combat human-trafficking after the U.S. State Department issued a report in June slamming Japan's efforts to crack down on the problem.

Tokyo subsequently adopted a plan to combat human-trafficking in December.

As Japan has no specific laws against human-trafficking, police have to use other laws related to immigration, prostitution, employment security and other areas to combat the problem.