How a love-lorn hacker brought Houston to a halt

A computer programmer who got into a row with an American woman in an internet chatroom allegedly crippled computer systems at the port of Houston in Texas.

Aaron Caffrey, 19, from Dorset, who suffers from Asperger's Syndrome, denies one charge of unauthorised modification of computer material.

Southwark Crown Court was told how the onslaught, on 20 September 2001, came at a time when US authorities were in a heightened state of alert.

Paul Addison, for the prosecution, said that Mr Caffrey's intended target was a female chatroom user called Bokkie, with whom he had argued over anti-American remarks she had made. Mr Caffrey was arrested in January 2002 and told police that he was being exploited by other hackers who planted evidence in his hard drive. But Mr Addison said data pointed to Mr Caffrey.

Mr Addison said that in order to prevent the attack rebounding it had to pass through a number of intermediary server systems, one of which operated in the port at Houston.

The scheduling computer systems at the port were bombarded with thousands of electronic messages intended to be forwarded to another address. The port's web service was inaccessible, putting shipping at risk because those responsible for helping ships navigate could not get the data they needed.