Nine tug crew were missing on Friday after a collision involving a Mercosul Line containership.
The 1,886-teu Mercosul Santos (built 2008) and the smaller vessel came together in the Amazon near Obidos, Brazil.
The accident happened while the tug was pushing several barges owned by Bertolini on 2 August, the Globo daily reported.
Two of the 11 crew were rescued.
The Brazilian navy is carrying out search and rescue operations, including divers at the scene.
The boxship anchored at the site. It had been heading to Manaus.
The incident was the second to hit the CMA CGM-controlled line this week.
A crewman on the 2,478-teu sistership Mercosul Manaus (built 2009) suffered serious burns when a pipe ruptured on Tuesday.
