Investigators are looking at a possible design flaw in some Seagate hard drives found in MacBooks and MacBook Pros, according to Techworld on Friday. The problems leads to catastrophic data loss.

The problem is suspected with Seagate 2.5-inch SATA drives made in China and loaded with firmware version 7.01. Model numbers affected include ST96812AS and ST98823AS. The read/write head can detach and cause a catastrophic failiure of the drive and loss of all data.

"There is absolutely, definitely a flaw with these drives," said Duncan Clark, the managing director of Retrodata in the UK. "I have seen enough to know there is a problem with them ... any Apple Mac that uses a 2.5 inch drive is at risk."

While the number of reported instances is still small, and Mr. Clark conceded that one would need to see several hundred or thousand drives fail in this way to be sure of a design flaw, the problem reports are still being looked at carefully.

Also, it is not clear if the problem is related to Macs shipped only to the UK or worldwide. In any case, MacBook owners would be wise to check their drive models and be sure their daily backup procedures are firmly in place.