Hunt for crew missing after bridge collapse

RECOVERY efforts have resumed for six workers who are presumed dead after a cargo ship hit a pillar of the Francis Scott Key Bridge in Baltimore, Maryland.

The collision occurred in the early hours of Tuesday after the ship lost its steering capability before it hit a pillar of the US city's Francis Scott Key Bridge.

Audio from first responders reveals a scramble to halt traffic just before the crash.

The bridge is an important link in the region's transport infrastructure, and its collapse is expected to snarl commuter traffic and disrupt a vital shipping port for some time.