Anton Febles, a 28 year old Level 3 sex offender, had been convicted a decade ago ofindecent assault and battery on a teenager.  Febles failed to register with authorities andpolice were told that he may be carrying a gun.  US Marshals assigned to the Fugitive TaskForce's Sex Offender Apprehension Program, or SOAP, waited for any sign that Febles was in a houseon Blue Hill Avenue.  Febles had been charged in 2005 with aggravated rape of a teenager,though he eventually pleaded guilty to a lesser charge of indecent assault and battery, and he wassentenced to 2 1/2  years in prison followed by five years of probation.  After two hoursof waiting, the deputies and police were able to get inside the apartment house.  Febles, whohad evaded them for hours, finally walked out, apparently defeated.  Through the SOAP, the USMarshals Service have created a partnership with Boston police, a first of its king, full-time taskforce that tracks down convicted sex offenders like Febles who have failed to register with stateauthorities.  The unit was enacted under the mission of the 2006 Adam Walsh Child Protectionand Safety Act, and it has become increasingly active in recent years as federal officials ramp upefforts to target sex offenders like rapists, sex traffickers, those involved in child pornographyand the exploitation of children. 
Some of the offenders recently captured include:
- Terrance Brown, convicted in 2004 of indecent assault and battery on a 14 year old,raised suspicions when he later traveled to North Carolina with a child.  He was convicted infederal court of failing to register as a sex offender, and was sentenced in 2012 to two years inprison, followed by 10 years of probation.
- Stephen Mitchell was convicted in 1995 of indecent assault and battery on a 12 yearold, and was charged in state court in 2009 with rape of a child and disseminating obscene materialto a minor.  He fled the 2009 charge, and was tracked down in Georgia.  He was sentencedto two years in federal prison for failing to register as a sex offender, and ultimately pleadedguilty and was sentenced to four years for the 2009 charge of rape of a child.
- Gary Dix was convicted twice of indecent assault and battery on a child under 14, in1987 and 1993, as well as open and gross lewdness, but he failed to tell that to authorities inMaine, where he had been living with his new girlfriend.  He was found and arrested, andpleaded guilty in federal court in Boston to failure to register as a sex offender, and is slatedto be sentenced June 4.