City police are planning to crack down on what amounts to modern-day slavery.

The Justice Department (search) on Tuesday announced a $450,000 grant for a special District of Columbia task force to combat human trafficking (search).

Assistant U.S. Attorney General Alexander Acosta described finding a 14-year-old immigrant from Mexico with a teddy bear on the night stand of a trailer with only a twin bed and a screen.

"She was held there and forced to have sex with 30 men per day," Acosta said. "It happens more than Americans realize it. We estimate there are 15,000 individual victims a year."

In July, federal prosecutors won convictions in the case of two men forcing teens to work as prostitutes in D.C. In a separate case, two other defendants were convicted of running a prostitution (search) ring of 30 women -- including girls as young as 14 -- through a Web site.

Federal officials credit an alert D.C. police officer for spotting an exploited 12 year-old girl, and say the eyes of the public and medical personnel are also important.

Acosta said since 2001, federal prosecutors have charged 166 people with trafficking and have a 100 percent conviction rate.

"It sounds like good numbers, but we can do a lot more," Acosta said.

D.C. Metropolitan Police Chief Charles H. Ramsey (search) said he does not know how prevalent human trafficking is in the city, but that even one victim is one too many.

Ramsey said the grant money will be used for overtime and training officers to identify the signs of human and trafficking. Some money will also go for social services to help the victims.

Nicole Streeter, Director of Legal Services for Covenant House (search), which helps homeless, runaway and at risk youth, said the task force is long overdue.

Acosta said prosecuting these crimes is just the beginning, because the victims will need help to "stay safe and help heal."

As for laws that would crack down on the demand for child prostitutes by prosecuting the customers, federal prosecutors say that is a matter for state and local lawmakers.