1.   Computer hackers pose a serious threat to the security of computer systems and some of the activities in which they engage are potentially criminal in nature.

2.   And many lab employees remain unaware of the threats hackers pose to lab computer systems.

3.   But hackers pose a significant threat.

4.   Some hackers now pose as telecoms consultants, offering voice-mail security services.

5.   The ISP Security Consortium said hackers pose the biggest threat to the growth of online commerce, such as shopping via the Internet.