Image copyright EMMANUEL DUNAND

Internet marketplace giant Amazon reported a surprise profit for the second quarter in a row thanks largely to higher sales in the US.

Amazon, the world's biggest online retailer, reported profits of $79m (£51.3m), compared with a loss of $437m a year ago.

Another period of strong growth in its Amazon Web Services cloud business also contributed to the better result.

Total net sales rose 23.2% to $25.36bn. Its shares were 10% higher.

Worldwide Sales in North America rose 28.3% to $15.01bn.

Amazon has piled on revenue growth since it started up but only recently began booking profits.

Instead, the 20-year old Seattle-based company has reinvested profits in order to expand.

Net sales from Amazon Web Services, which has more than one million active customers in 190 countries, rose more than 78% to $2.09bn in the three months to the end of September.

Amazon has made a strong growth forecast - if vague as to quite how strong - of between 14-25% for the Christmas sales period.

The online retailer reported a $92m profit for the three months to 30 June, surprising investors who had expected another loss.