Attacks on company Internet sites in 2001 increased 50% compared with 2000, according to two new reports on Internet security released today.

In a story first reported by the Washington Post newspaper, the CERT Coordination Center - a government-funded computer security response team based at Carnegie Mellon University - said that companies reported 52,658 breaches of Internet security last year, up over 50% from 2000.

In another study, released by Internet security consulting firm Riptech of Alexandria, VA, attacks on Internet web sites numbers 128,678 between July and December of last year. Riptech said that 41% of the attacks were labeled "critical," meaning that company computer systems were comprised. About 12.7% of those attacks were of an "emergency" nature, which meant that computer systems failed or were shut down as a result of the attacks.

The source of cyber attacks is limited to just a few countries, said Riptech's report, with about 30% starting in the United States. In terms of number of attacks launched per Internet user, Israel was the largest base for cyber attacks over the last six months of 2001.