The company plans to allocate a record amount to capital expenditures to build artificial-intelligence infrastructure.

By Greg Bensinger, Deborah Mary Sophia (Reuters) -Amazon.com investors drove shares down sharply on Thursday due to weakness in the retailer's cloud computing unit and lower-than-expected forecasts for first-quarter revenue and profit.

Amazon shares slid after the online-retail and cloud-services giant offered a first-quarter outlook that came up short of Wall Street’s expectations while forecasting bumpy trends in its cloud business.