What caused the Dali to slam into Baltimore's Francis Scott Key Bridge? What we know about what led up to the collapse

Shocking video showed the moment a massive cargo ship collided with Baltimore's Francis Scott Key Bridge early Tuesday morning, sending parts of the decades-old suspension bridge, along with people and vehicles, into the Patapsco River. 

Six people who were on the bridge are missing and presumed dead, officials said late Tuesday. Two others were rescued from the water. All eight were construction workers who were repairing potholes on the bridge, officials said. There were 22 Indian nationals, including two pilots, aboard the cargo ship. 

Investigators and officials are now crafting a timeline of events, including what caused the Singapore-owned vessel, called the Dali, to hit the bridge just minutes after leaving port. Here's what we know so far.