Two years before a deadly listeria outbreak, U.S. inspectors warned that conditions at a Boar’s Head plant posed an “imminent threat” to public health, citing extensive rust, deli meats exposed to wet ceilings, green mold and holes in the walls.

But the U.S. Agriculture Department did not impose strict measures on the plant, in Jarratt, Va., which could have ranged from a warning letter to a suspension of operations.

Since then, other inspections found that many of the problems persisted, but again, the plant continued to process tons of beef and pork products, including liverwurst.

Genome sequencing tests by public health officials in New York and Maryland tied a strain of listeria found in Boar’s Head liverwurst to the bacteria from people who died or fell ill, according to the Centers for Disease Control and Prevention.

The company recalled its liverwurst late in July. Days later, Boar’s Head expanded the recall to cover more than 3,500 tons of meat — including ham and other items made in the Jarratt facility, one of several it operates.

Production at the meat processing center in a rural part of the state has been temporarily stopped. Boar’s Head said it was disinfecting the plant and trying to determine the cause of the suspected contamination. Nine elderly people have died and dozens were hospitalized in the worst listeria outbreak in years.