The New York Times reports that federal investigators have opened a criminal investigation into accusations that some California spinach growers and distributors failed to take adequate measures to ensure that their spinach was safe before selling it.

Yesterday, agents of the FBI and the Office of Criminal Investigations in the FDA carried out search warrants

As growers are getting their spinach back on the market, federal investigators will try to capture wild pigs and test them for the E. coli strain that killed one person and sickened dozens of others across the country in the national spinach-related outbreak.

Several farms implicated in the E. coli outbreak also have cows on

California officials have discovered E. coli in cattle feces on pastures near farms being investigated as possible sources of spinach contaminated with the bacteria, which caused a nationwide outbreak of food poisoning.

Reuters reports that state investigators have obtained eight samples of cattle feces testing positive for E. coli. The samples are being retested to

Fresh spinach started trickling back onto local grocery stores shelves this weekend and will slowly continue its produce section homecoming throughout the week, according to the Monterey County Herald.

The news from the Monterey County Health Department this weekend saying local spinach was safe to sell again has been good news for producers such as