Amazon said this week its facial recognition software can detect a person’s fear.

Rekognition is one of many Amazon Web Services (AWS) cloud services available for developers. It can be used for facial analysis or sentiment analysis, which identifies different expressions and predicts emotions from images of people’s faces. The service uses artificial intelligence to “learn” from the reams of data it processes.

The tech giant revealed updates to the controversial tool on Monday that include improving the accuracy and functionality of its face analysis features such as identifying gender, emotions and age range.

“With this release, we have further improved the accuracy of gender identification,” Amazon said in a blog post. “In addition, we have improved accuracy for emotion detection (for all 7 emotions: ‘Happy’, ‘Sad’, ‘Angry’, ‘Surprised’, ‘Disgusted’, ‘Calm’ and ‘Confused’) and added a new emotion: ‘Fear.’”

Artificial intelligence researchers have invested plenty of resources to try and read a person’s emotions by analyzing their facial features, movements, voice and more. Some tech companies involved in the space include MicrosoftAffectiva and Kairos.