Amazon.com Inc. has rolled out a service that allows Whole Foods Market Inc. customers in Sacramento, Calif., and Virginia Beach, Va., to order groceries online and pick them up "in as little as 30 minutes."

Members of Amazon's Prime service can place their grocery orders — such as fresh produce, dairy and everyday staples — through the Prime Now app and choose the pickup option at checkout.

A Prime Now employee will load customers' purchases into their car when they arrive at a reserved pickup spot.

The service, available daily from 8 a.m. to 10 p.m., is free for purchases of at least $35 that will be collected in an hour, while pickup in 30 minutes costs $4.99.

Amazon plans to expand the program to more U.S. cities throughout 2018.

The announcement follows the company expanding its Whole Foods delivery service to parts of Florida and New York.

Earlier in 2018, Amazon launched its in-car delivery service that allows customers to have their packages delivered to their cars.