Updated

Sex offenders in Maryland have begun receiving paper signs in the mail that read "No candy at this residence," which they must post on their front doors or possibly face a parole violation.

The signs began arriving last week in the mailboxes of the about 1,200 violent and child-sex offenders across Maryland. The signs were accompanied by a letter explaining they must stay at home, turn off outside lights and not answer the door on Halloween.

Maryland is also distributing pamphlets statewide to warn families to stay away from homes with the pumpkin signs.

"Halloween provides a rare opportunity for you to demonstrate to your neighbors that you are making a sincere effort to change the direction of your life," the letter to sex offenders reads.

"Because Halloween is a holiday in which large numbers of children interact with strangers, the concern among parents and other community members about sexual offenders in their neighborhoods is naturally intensified during this time of year," Patrick McGee, interim director of the state's Division of Parole and Probation, wrote in the Oct. 1 letter.

Maryland, which began the program in 2005, is among a number of states placing Halloween restrictions on sex offenders. Maryland's regulations are almost identical to those adopted in Missouri, where four convicted sex offenders and the American Civil Liberties Union are challenging the state law in federal court.

"We've had very good results," Wonda Adams, said a supervisor at the Parole and Probation Division and coordinator of the Halloween watch program.

"Our goal is public safety, and in keeping with that we need to make sure that the individuals under our supervision are provided with the enhanced supervision that we're committed to."