Bank hacks were work of Iran, officials say

The attackers hit one U.S. bank after the next. As in so many previous attacks, dozens of online banking sites slowed, hiccupped or ground to a halt before recovering several minutes later.

But there was something disturbingly different about the wave of online attacks on U.S. banks in recent weeks. Security researchers say that instead of exploiting individual computers, the attackers engineered networks of computers in data centers, transforming the online equivalent of a few yapping Chihuahuas into a pack of fire-breathing Godzillas.