Amazon is building the suspense around its mysterious launch event scheduled to take place in Seattle, June 18, but hints point toward the launch of the company's first smartphone.

Amazon, the biggest online retailer, is doing well with its suspense game so far. The retail giant announced a launch event in Seattle on June 18, but kept the details under wraps. To raise the curiosity quotient, Amazon released a teaser video of a group of people responding to an unseen device. By the looks of it, Amazon is hinting at its rumored 3D smartphone that will be shown at the event, The Next Web reports.

To add more spice to the event, Amazon has updated a header image on the announcement page, which shows the back of a device featuring the company's logo on it. The same picture is pinned to Amazon's official Twitter page, which confirms the event will showcase the next Amazon device.

Rumors of Amazon working on a 3D smartphone have been making the rounds since April. Last month, BGR leaked images of the handset's design, which showed a full-touch display, earpiece and a single home button at the bottom. The left side of the phone showed a SIM card slot and three buttons, presumably for volume and lock functions. The rear side of the device had an Amazon logo and two grilles at the bottom to serve as microphone input and speaker output. A micro USB charging slot separated the two grilles. The leaked image also showed a camera and a flash on the top right hand corner, identical to the one found on iPhones but on the opposite side.

The Amazon smartphone is also rumored to feature unique 3D effects and gesture controls. Other leaked specs round off the handset's features with a 4.7-inch 720p display, 2GB RAM, quad-core Qualcomm Snapdragon processor and a heavily customized Android OS.

The addition of a smartphone will expand Amazon's portfolio of electronic gadgets that include Kindle e-reader, Kindle Fire tablets and a Fire TV set-top box. While the event is less than two weeks away, Amazon has an open invitation for the event in Seattle. Just fill out the form here and Amazon will notify.