A criminal ring of mothers and daughters is running \"sweetheart scams\" that con older men out of their money, Chicago-area law enforcement investigators warned. The scams have cost victims hundreds of thousands of dollars, the Chicago Tribune reported Thursday. \"There [are] people out there attempting to prey on folks,\" Cook County Sheriff Tom Dart said. \"They\'re very methodical in what they\'re doing, and this is a part of a well-thought-out plan.\" The cons were dubbed the \"sweetheart scams\" by investigators. The sheriff\'s office said the operation involves a woman in her late 20s to late 40s approaching a man at least 60 years old, striking up a conversation, which usually leads to a date. The woman seduces the mark, implying a relationship is blossoming while discussing a financial crisis that needs resolving -- leading to the man giving her money, the sheriff\'s office said. Investigators said one man who gave away nearly $400,000. \"These sweethearts are very cunning,\" Velencia Myton, supervisor of protected services at an area Council on Aging, told the Tribune. \"They pick on men who are vulnerable and lonely. Of course it strokes his ego. … He\'s back in the game again. This is what [the women] are counting on.\" Myton said investigators noticed an increase in the number of reported scams during the past six months. The conned men rarely prosecute, readily admitting they willingly gave money to the women.