The overnight collapse of Baltimore's Francis Scott Key Bridge drove a surge in online conspiracy theories Tuesday, many of them promoted by "verified" accounts with huge followings on X.

Why it matters: Rampant misinformation during mass casualty events is not a new phenomenon. But under Elon Musk's ownership of X, the platform has changed from an essential real-time news source to a breeding ground for conspiracy theories.

Driving the news: Federal and state authorities said Tuesday there's no evidence that terrorism played a role in the collapse of the 1.6 mile-long bridge, which was struck by a container ship at around 1:30am ET Tuesday.

• The crew of the Singapore-flagged Dali issued a mayday call before striking the bridge and notified authorities that it was experiencing a power issue, according to Maryland Gov. Wes Moore.
• Paul Wiedefeld, Maryland's transportation secretary, said eight members of a construction crew were making repairs to the bridge at the time of the collision.

What they're saying: "Everything so far indicates that this was a terrible accident. At this time, we have no other indication, no other reason to believe there's any intentional act here," President Biden said in remarks Tuesday afternoon.

Zoom in: Within hours, X accounts with hundreds of thousands of followers were promoting baseless claims that the Dali had been the victim of a cyber-attack or had intentionally rammed into the bridge.

• Much of the misinformation was being pushed by "verified" users who pay for a premium subscription that boosts their posts.
• Some verified right-wing accounts speculated that corporate diversity and inclusion initiatives were to blame for the disaster — a claim also embraced during a spate of recent aircraft safety issues.
• Several antisemitic accounts with blue check marks claimed that the "attack" was perpetrated by Israel.

The other side: Community notes, a system on X that allows users to add context to misleading or false posts, flagged some of the conspiracy theories as baseless.

The big picture: Bad actors often take advantage of breaking news events to sow discord and confusion while details are still scant, with cause and intent typically the biggest targets for misinformation.

• Everyday social media users who aren't seeking to intentionally spread falsehoods then amplify the rumors when they see them going viral on social media.
• Over the last several years, most platforms have dramatically reduced content safety and moderation teams that could help respond to these types of misinformation events in real time, citing costs and inefficiency.
• Musk — a self-proclaimed free speech absolutist — has come under especially intense criticism for allowing misinformation to go unchecked on X as long as it doesn't break the law.

Between the lines: Social media companies continue to be haunted by their handling of the Hunter Biden laptop controversy and the COVID-19 lab-leak theory, which contributed to widespread distrust among conservatives.

• Platforms fear that taking quick action to label certain political claims as false or misleading could come back to bite them.
• Ahead of the 2024 election, Big Tech companies have largely walked back policies instituted to curb misinformation around COVID-19 and the 2020 election.

The bottom line: Extreme polarization and a historic low in Americans' trust in media have created a perfect environment for misinformation to flourish in moments of chaos.