Amazon has reached an agreement to acquire Ring, the Santa Monica, Calif.-based maker of video cameras, doorbells and other smart home technologies, GeekWire has learned. The companies are expected to announce the acquisition this afternoon.

The surprise acquisition marks the latest move by the Seattle-based tech giant into the smart home technology market. Financial terms were not disclosed, but Reuters puts the deal at more than $1 billion. Amazon is expected to treat the Ring deal similar to past acquisitions such as Zappos, Twitch and Audible, pursuing product and feature integrations where appropriate but maintaining the Ring brand and largely allowing the company to continue operating as it has in the past.

“Ring is committed to our mission to reduce crime in neighborhoods by providing effective yet affordable home security tools to our neighbors that make a positive impact on our homes, our communities, and the world,” a Ring spokesperson said in a statement. “We’ll be able to achieve even more by partnering with an inventive, customer-centric company like Amazon. We look forward to being a part of the Amazon team as we work toward our vision for safer neighborhoods.”

Amazon is positioning its Echo smart speaker, with the embedded Alexa voice assistant as a home technology hub.

“Ring’s home security products and services have delighted customers since day one,” an Amazon spokesperson said in a statement. “We’re excited to work with this talented team and help them in their mission to keep homes safe and secure.”

Ring makes WiFi enabled doorbells equipped with cameras that detect when someone is at the door. The smart doorbell rings users’ tablets or smartphones through an app that lets them see audio and video and talk to the person at the door, wherever they are.

The company’s mission is to reduce crime in neighborhoods while providing affordable options that work for every home. It started with a single video doorbell, now priced at $179, and has since expanded to offer several different versions as well as security systems and cameras.

Just last month Ring acquired a startup called Mr. Beams that makes WiFi-enabled LED lighting with motion-sensing capabilities.

Amazon previously invested in Ring via its Alexa Fund, which helps companies building skills and products for the tech giant’s digital brain.

This past October Amazon unveiled its own $119.99 home security camera, Cloud Cam, with a companion Amazon Key app that works with smart locks to let Amazon Prime members give house cleaners, dog walkers, package delivery companies and other service providers access to their homes. Amazon sells an Amazon Key In-Home Kit, including an Amazon Cloud Cam and a compatible smart lock, for $249.99.

The Cloud Cam competes with a variety of security cameras on the market, including Ring, Arlo and Google’s Nest Cam. It can be used with subscription plans for extended storage and other extra features, ranging from $7 to $20 a month, or a free plan offering 24 hours of cloud storage.

The technology addresses the ongoing challenge of package theft and provides an additional benefit for Amazon Prime members. The concept, however, is not popular with some people concerned about Amazon controlling access their front doors.

Ring rolled out integration with Amazon’s Alexa voice platform in June, connecting select products to the Echo Show and Fire TV devices. “By working with Alexa, Ring is making home security even simpler and more convenient. Now, you not only have the power of home security at your fingertips, you can also have it at the sound of your voice,” Ring noted in a blog post. The skill has a 2-star rating.

Ring CEO and Chief Inventor James Siminoff appeared on the show Shark Tank in 2013 to raise money for his product, which was called Doorbot at the time. He failed to make a deal on the show, but since then, the company has raised more than $209 million, according to CrunchBase, including a $109 million round in January 2017.

In an update to the show last November, Siminoff said the company is valued at more than $1 billion and employed at the time more than 1,300 people and offered 10 core products, sold in more than 16,000 stores.

Ring counts Virgin CEO Richard Branson as an investor. Branson described in a 2015 blog post what he liked about the company.

“I am an investor in Ring, and while the product is exciting and its mission to reduce crime in communities is important; what I found so interesting was the story of the young entrepreneur – James Siminoff – behind it. Like many others at the start of their journey, James tried and failed to raise money for his idea – for him it was on the popular US show Shark Tank. Unbowed, he went on to develop the product and the business and just raised a substantial fundraising which I joined.”

In December Amazon acquired Blink, a startup based in Andover, Mass. that makes wire-free smart security cameras and video doorbells.