DENVER -- Before opening fire at his Washington state high school -- shooting five classmates and then killing himself -- Jaylen Fryberg sent out a series of cryptic Tweets.
The 15 year old posted: "May as well die now" and "I know it seems like I'm sweating it off -- but I'm not, and I'll never be able to."
"That's certainly a red flag," said Dr. Larry Curry, a Denver family therapist, adding that teens often turn to social media, posting similar messages in a cry for help.
"'I don't think I can go on' or 'no one really cares,' those are the kind of phrases that pop out," said Curry. "I would say those are good clues."
Now those telling clues on Twitter can be tracked with a new web-based app, Samaritan's Radar.
The free app uses algorithms to track language used by people you follow on Twitter, to alert you when they use phrases that may mean they need help.
"I think that's excellent," said Mary Lou Torres, a suicide prevention counselor based in Denver who recommends the app, especially for parents.
"Parents are always so busy with their own lives ... That was my problem back then," said Torres, whose daughter, Liza took her own life in 1985 at just 18 years old.
"I didn't realize what my daughter was going through," said Torres. "I thought she was very happy."
Torres hopes others can use tools like Samaritan's Radar, to reach out to those who need support before its too late.
"You may be that one person that may save them from it," said Torres.
To sign up for the free app, visit their website.AlertMe