For the most part, Twitter is a sphere for users to express their thoughts freely.

In most cases, these thoughts are nothing more than harmless commentary on menial things like traffic jams, or something silly that happened on the Starbucks line. However, there are exceptions?—?and it seems that a gruesome exception to this rule occurred last week, after one user foreshadowed the eventual murder of his roommate to all of his followers.

Twenty-one-year-old Zachary Penton, who is suspected of tweeting under the handle @Zac_Penton, was arrested Sunday in his Gilbert, Arizona home after his roommate?—?41-year-old Daniel Garofalo?—?was found shot dead inside. Penton himself called authorities, explaining that a fight escalated and resulted in him pulling the trigger. According to Arizona’s ABC15, Penton was taken into custody shortly after, where he was booked on a murder charge.

What makes this story especially bone-chilling is that Penton tweeted this just two days before Garofalo’s murder:

Although Gilbert police still haven’t confirmed Penton as the man behind this tweet, it seems quite likely given Penton’s name and the handle itself. Assuming this tweet was, in fact, Penton’s, it’s alarming that news of the tweet’s disturbing content failed to reach authorities before Penton pulled the trigger. But this is the danger that Twitter—and most other social media platforms—pose: It’s hard to discern someone’s true intentions over the internet.

Just like certain non-verbal cues and things like sarcasm get lost over the internet, more serious things can get overlooked, as well. Penton’s tweet is a dramatic example of this.

Slate went as far as including a search query of Penton’s suspected handle along with the keyword “roommate,” so you can get a full report of anything he tweeted relating to his roommates. As you’ll see, Penton was not shy about the trouble he encountered trying to find someone to live with.

Penton’s most disturbing tweet was one that he posted back on June 3rd, in which he—almost mockingly—expressed how simple it was for him to obtain a firearm: an all-too-common trend in this country.

He also retweeted this controversial post just days before his own murder confession.

According to ABC15, Penton maintains that he was scared for his safety following his final dispute with Garofalo. His bond is set for $750K.