(Updates number of tanks on fire)
RIO DE JANEIRO, April 5 (Reuters) - A fire at a fuel storage facility near Brazil's largest port Santos entered its fourth day on Sunday as 110 firefighters worked to stop the flames from spreading further, the local fire department said.
Six fuel tanks run by Ultracargo, owned by Brazil's Grupo Ultra, were hit since the blaze started on Thursday morning, sending a column of thick black smoke into the air. Two of them were still burning late on Sunday, the fire department and Ultracargo said.
Firefighters said there was little they could do to extinguish the flames before most of the fuel was consumed. Instead, they were focusing on dousing nearby tanks to keep the fire from spreading.
Traffic was diverted around the site of the blaze, blocking one of the roads to the port.
Trucks carrying soybeans and other commodities were still able to deliver their goods via a second entrance, a spokeswoman for the Santos port said. She added that only two of the port's docks were out of service due to the fire, while the other 53 were operating normally. (Reporting by Walter Brandimarte)