SEOUL — South Korean police raided clubs on Itaewon’s Hooker Hill on Tuesday night as part of a nationwide crackdown on prostitution, but they found "nothing suspicious" and made no arrests, a Yongsan police spokesman said Wednesday.

The spokesman said closed-circuit televisions installed by bar owners on street corners throughout Hooker Hill, an area famed for its prostitution, made it difficult to catch sex offenders.

"They can watch us, and all of our movements and steps in advance before we start patrolling the area," he said.

Hooker Hill is near U.S. Army Garrison-Yongsan, and most of the clubs are off-limits to U.S. troops.

The South Korean media reported that two 46-year-old South Korean women were sentenced to eight months in prison on Tuesday, the first to be sentenced as part of the crackdown, which began in July and runs through the end of the month.

One of the women owned an illegal massage parlor in Dongdaemun, outside the U.S. military’s Camp Red Cloud. She was fined 100 million won, approximately $80,800, for unlawful profits she earned through running the business and acting as a prostitute. She earned about 20,000,000 won, or $16,000, each month and had five to six customers a day in the past nine months, according to South Korean media reports.

The other woman, an employee, was sentenced to 120 hours of social work.

Their sentences were suspended for three years.

Court officials were unavailable for comment Wednesday.