Those obstacles included a recall over allegations of unintended sudden acceleration by Toyota vehicles, a problem that raised questions about the company's quality control, safety measures and customer service.

WSJ: Toyota Overhauls Management

Obama and other supporters of stronger gun control measures say all possible efforts must be made to address what they call a chronic and growing problem of gun violence, particularly involving vulnerable targets such as students.

CNN: Obama still backs new gun ban; top senator less certain

The farm, which is popular with families and attracts 2, 000 visitors a day at peak times, said suitable control measures were in place and it would not reopen until it had got to the root of the problem.

BBC: Another child treated for E.coli