Immediately after the mass shooting at a Florida high school last week, hundreds of Twitter accounts turned their focus "almost on a dime" to amplify the events of the tragedy, Jonathan Morgan told CNBC on Tuesday.

According to The New York Times, those Twitter accounts are suspected of having links to Russia. Before the shooting that left 17 dead, many of those accounts had been focused on the investigation into Russian meddling in the 2016 election, the paper reported.

While the accounts first focused on breaking news, they quickly turned to extreme pro-gun rhetoric as well as advocating gun control, said Morgan, CEO of New Knowledge, which tracks online disinformation campaigns. They also spread conspiracy theories, he added.

"It's hard to say exactly who's behind all of the content that we see but what we can say is that there [are] multiple networks of accounts, they're manipulating the conversation and they are playing both sides," he told "Closing Bell."