Bank computer intrusions are becoming more common and more costly, reports Washington Post blogger Brian Krebs, citing a report by the Federal Deposit Insurance Corp.

The federal entity, which oversees and insures more than 9,000 U.S. financial institutions, issues a quarterly Technology Incident Report, based on suspicious activity reports. Banks are required to file such a report for each suspicious or fraudulent transaction of $5,000 or more.

In the most recent report, based on the second quarter of 2007, the FDIC found rapid growth in financial crime aided by computer intrusions. And it reported the mean loss per incident of computer intrusion was about $29,630, nearly triple the $10,536 in the same period in 2006.

Krebs blogged Friday on similar growth in computer intrusion on Wall Street.