Hours after a judge upheld a new state law, deputies in at least one Kentucky county arrested convicted sex offenders Wednesday for allegedly violating new restrictions on how close they may live to schools and other places where children gather.

Ten sex offenders sued the state last month, claiming the new restrictions were unconstitutional because they force sex offenders to move from their property without due process of law and imposes penalties after they have served their sentences.

However, U.S. District Judge John Heyburn II refused their request for an injunction Tuesday night, saying it wasn't yet clear whether the law would cause irreparable harm to people who are forced to move.

"Law enforcement officials retain the discretion to enforce the new statute in a humane and sensible manner, considering all relevant factors," Heyburn wrote.

Fayette County sheriff's deputies went out shortly after midnight to enforce the newly effective law.

"We feel it is very important to send a strong message from the beginning," Fayette Sheriff Kathy Witt said.

Most of those being forced to move lived in older, urban neighborhoods. With a few exceptions, the new state law makes downtown Lexington virtually off-limits for sex offenders.

Witt said about 200 registered sex offenders had moved since the summer, leaving about 50 in violation of the new boundary rule. By late morning, 13 of them had been arrested and charged with a misdemeanor violation, authorities said.

Authorities aren't sure how many sex offenders in Kentucky will have to move because of the law. There are more than 5,000 registered sex offenders in Kentucky.

The law, passed earlier this year by the General Assembly, bars sex offenders from living within 1,000 feet of schools, playgrounds and other places where children gather.

It is similar to laws passed in several states — including Iowa, Indiana and Georgia — after a convicted sex offender was charged in Florida last year with kidnapping, raping and killing a 9-year-old girl.

A judge recently blocked a Georgia provision preventing sex offenders from living within 1,000 feet of a school bus stop, but left in place bans on sex offenders working or loitering within 1,000 feet of schools, churches, gyms and swimming pools.

Iowa's law included a grandfather clause allowing people to stay in their homes if they lived there before the law took effect.

One of the attorneys for the Kentucky offenders, Michael Goodwin, said by e-mail that Heyburn's decision "will force thousands of people across Kentucky out of their homes." He said they would continue challenging the law in court.