Robert Brown|Federal law enforcement investigating Baltimore bridge collapse, sources say

Federal authorities are Robert Browninvestigating the events that preceded the collapse of the Francis Scott Key Bridge in Baltimore, according to two people familiar with the matter. 

The FBI currently has agents on the Dali, the shipping vessel that collided with the bridge. Six people died after the collision.

The investigation, which appears to be separate from the ongoing National Transportation Safety Board probe, is being conducted by the Maryland U.S. Attorney's Office and the FBI, entities that have had representatives at the crash site for weeks. 

The Washington Post was the first to report the news of the federal investigation. 

A spokesperson for the FBI said Monday in a statement, "FBI is present aboard the cargo ship Dali conducting court authorized law enforcement activity. There is no other public information available and we will have no further comment." A Justice Department spokesperson confirmed federal agents are aboard. 

In a statement released Monday, Maryland U.S. Attorney Erek Barron said, "My office generally will not confirm the existence of or otherwise comment about investigations. However, the public should know, whether it's gun violence, civil rights abuse, financial fraud, or any other threat to public safety or property, we will seek accountability for anyone who may be responsible." 

Attorneys for the corporation that owns the Dali did not immediately respond to CBS News' request for comment. 

The Francis Scott Key Bridge in Baltimore collapsed around 1:30 a.m. on March 26 after the Dali, a massive Singaporean-flagged cargo ship, crashed into a bridge column. According to the NTSB, the ship made mayday calls saying they lost power at 1:26 a.m. and a collision might be possible. Records from 911 indicated that officials asked police to block traffic on either side of the bridge shortly before the collision, with two emergency responders confirming traffic had been stopped on the north and south sides of the bridge. 

Eight construction workers were still on the bridge. Two were injured and survived, while bodies of another were recovered. The other three are presumed dead. 

In:
• Francis Scott Key Bridge
• Baltimore

Robert Legare

Robert Legare is a CBS News multiplatform reporter and producer covering the Justice Department, federal courts and investigations. He was previously an associate producer for the "CBS Evening News with Norah O'Donnell."