By Avril Ormsby

LONDON (Reuters) - HSBC said on Monday it has lost a computer disc containing details of nearly 400,000 customers.

The disc contains the names, dates of birth and insurance cover levels of 370,000 people who hold life assurance policies at the bank.

It does not contain addresses or bank account details, HSBC said.

"The data disk lost by HSBC contains no address or bank account details for any customer and would therefore be of very limited, if any, use to criminals," it said in a statement.

The data was password-protected, it added.

The disc went missing, it said, after being sent via Royal Mail courier from the group's offices in Southampton to the reinsurer Swiss Re at the beginning of February.

It is not clear at what stage of the journey the disc went missing.

"It has got lost between A and B," said HSBC spokesman James Thorpe. "There is no reason to suppose that the disk has fallen into the wrong hands."