Whereas big attacks once used tens of thousands of zombie computers, this year's assaults on American banks employed only about 2,500.

在大规模的攻击中，黑客们曾动用成千上万的僵尸计算机，然而，今年对美国银行的攻击只不过调动了2500僵尸大军而已。

They use zombie computers. Maybe it was that?

他们用僵尸电脑 可能是这个原因？

The hacker allegedly used malware attacks to build up a network of thousands of zombie computers which were then used to illegally divert money from accounts, leaving next to no trace behind.

据悉这名黑客利用恶意攻击建立了包含数千台僵尸电脑的网络，这些电脑被用来从账户中非法转移资金，几乎不留下任何痕迹。