Story highlights A cryptic tweet last August refers to the Boston Marathon

2 friends of suspect Dzhokar Tsarnaev tell CNN this is his Twitter account

Hours after the bombing, he tweeted "stay safe"

He tweeted that a photo of an alleged Boston bombing victim was fake

Boston bombing suspect Dzhokar Tsarnaev has tweeted since the Boston Marathon bombings on what two friends of his tell CNN is his Twitter account.

His tweets included one at 1:43 a.m. Wednesday that said, "I'm a stress free kind of guy."

On Monday at 8:04 p.m. -- hours after the bombings -- he tweeted a quote from rapper Jay-Z and a 1970s R&B song, "Ain't no love in the heart of the city." The tweet added, "stay safe people."

Shortly after midnight, on Tuesday morning, he tweeted, "There are people that know the truth but stay silent & there are people that speak the truth but we don't hear them cuz they're the minority."

Tsarnaev uses the handle "J_tsar" and does not describe himself in the profile, which reads only, "Salam aleikum," a greeting among Muslims. The profile photo is the face of a lion with its mouth open, baring its fangs.

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He has tweeted a dozen times since the bombing.

The most recent tweet is one he retweeted on Wednesday from Mufti Ismail Menk, who identifies himself as a Muslim scholar. "Attitude can take away your beauty no matter how good looking you are or it could enhance your beauty, making you adorable," the tweet reads.

Another tweet from Tsarnaev on Tuesday was a quote from rapper Eminem: "Nowadays everybody wanna talk like they got somethin to say but nothin comes out when they move their lips; just a bunch of gibberish."

After another Twitter account posted a photo Tuesday saying it showed a man who was going to propose to his girlfriend at the marathon in Boston and found her dead, Tsarnaev tweeted a two-word response: "fake story."

Another of the suspect's tweets, an apparent response to someone else's tweet, reads, " and they what 'god hates dead people?' Or victims of tragedies? Lol those people are cooked."

Also Tuesday, Tsarnaev tweeted, "So then I says to him, I says, relax bro my beard is not loaded." On Friday, another Twitter user retweeted that message, and added the words, "But my backpack is."

Other items that he wrote, well before the Boston bombings, on the social media site may offer more details pertinent to the investigation.

On August 10, 2012, for instance, Tsarnaev wrote -- in response to another user -- "Boston marathon isn't a good place to smoke tho." The context of this conservation, however, was not known.