"ATF faces key resources challenges in staff attrition and system modernization," Ginger Colbrun, an ATF spokeswoman said in an e-mailed statement.
ATF, U.S. Attorneys blame sequestration, staffing woes for drop in gun prosecutions →
When reached later in the day and asked whether that was still true, she said, "We're following any and all leads related to this individual and firearms."
Evidence hints at deadlier plan in Conn. massacre →