On March 26, the Francis Scott Key Bridge in Baltimore went dark.

The container ship MV Dali, registered in Singapore left Baltimore harbor for Colombo, Sri Lanka. Forty minutes later, it suffered a complete blackout and began drifting from the shipping channel, issuing a “mayday” call three minutes later.

The lights came back on again but it was too late. At 1:28:45 a.m. EDT the 300-meter long, 48-meter tall ship struck a crucial support column holding up the bridge’s central span. Within seconds, the bridge broke apart in several places.

Of the six construction workers who were performing late-night road maintenance and were missing in the aftermath of the incident, two bodies were recovered while four others are presumed dead, as of Mar. 27. As it was late at night and the Maryland Department of Transportation suspended inbound bridge traffic upon the “mayday” call, other vehicles were not traveling on the span at the time.

The collapse of the bridge will have lasting economic implications for Maryland and the United States. Baltimore’s port, which the Dali had left, is one of the largest on the East Coast. About $80 billion USD in goods travels through the port each year. It is a particularly crucial port for a set of goods including transportation equipment, coffee, and sugar. The Key Bridge is also a crucial regional crossing for carrying hazardous materials, as they are restricted from using nearby tunnels.

The U.S. federal government has pledged to financially help with rebuilding the bridge, already sending an initial $60 million to the state of Maryland. There is precedent in how President George W. Bush passed emergency funding for Minneapolis after its I-35 bridge collapse in 2007.

As crews start the wreckage removal, conversations continue around responsibility and future implications on the U.S. supply chain.