“Government agents have recently uncovered numerous calls from hard-to-track prepaid cell phones, Internet-based phone service, prepaid phone cards and public pay phones in the United States to known al-Qaida locations overseas, federal officials said. The calls are one piece of a growing body of evidence pointing to the presence of suspected members of terrorist sleeper cells operating on U.S. soil, and a growing sophistication on their part to keep their communications secret, the officials said.” MSNBC