US electronics retailer Circuit City is to close after failing to reach a deal with its creditors and lenders, with the loss of 30,000 jobs.Liquidators will now sell off the firm's assets. The announcement comes two months after the firm was forced to seek bankruptcy protection.Some 567 Circuit City stores will now shut for the last time. About 155 stores had already closed in December.Circuit City vice chairman James Marcum said the decision was "regrettable".