SWAMPSCOTT – Police are investigating whether a lethal batch of heroin is responsible for the overdose death of a Swampscott man.Casey C. Washburn, 24, was found in a wooded area of Riverside Park in New Bedford on July 24.His death was the third suspected fatal overdose in New Bedford within a one-week period.His mother Kerry Washburn said the last time she spoke with her son was two days before his death.According to his mother, Casey was in a halfway house in New Bedford when he called her.”He was frantically asking to be moved,” she said. “He had only been there a few days and I never heard from him again.”Kerry, who described her son as a kid with a sense of humor and a big heart, said Casey started using drugs when he was 14 years old and still in high school. Kerry, who is an addiction specialist in Lynn, pointed out that when her son first started using drugs she didn’t recognize the signs.”One night he went out to take out the garbage and never came back,” she said. “He has been trying to get help for years. We know he did heroin and tried to get him help. The poor child – he’s at peace now. Heroin is rampant and destroying so many lives. We need programs for the parents to teach them what to look for.”Kerry said if there is one message she could get across to kids it would be “sick and addictive is not sexy.”Casey’s brother Pete Capuano, 33, urged others to learn from his brother’s death.”I just want to warn people- it’s awful,” he said. “I’ve read Casey’s letters. Just stay away from (drugs) at all times.”According to New Bedford Police Department Public Information Officer Lt. Jeffrey Silva, toxicology results are still pending and investigators are working to determine whether there are any connections between the three individuals. Kerry said she knew her son used heroin and had heard the heroin in the New Bedford area was extremely pure.”It’s something I was really worried about,” she said. “I was always afraid he’d overdose.”Capuano said whether the heroin was tainted or not, his brother’s death was criminal.”This is a crime from the word go whether it was a bad batch or not,” he said. “People have to stay away from this stuff.”Washburn’s family has established a memorial fund in his name and the funds will be dedicated to addiction recovery. Anyone who would like to make a donation should send it to: Casey Washburn Memorial Fund, c/o Eastern Bank, 405 Paradise Road, Swampscott, MA 01907.