WASHINGTON -- A federal warning letter said Bausch and Lomb failed to formally report nearly three dozen foreign cases of fungal eye infections later linked to one of its contact lens solutions.

The Food and Drug Administration said Bausch and Lomb didn't report the 35 serious injury reports by April 7, as required by law, after Singapore health officials had alerted the company about problems.

The failure came after the company suspended sales of its ReNu with MoistureLoc solution in Singapore.

It also came after the FDA had begun an investigation of the Greenville, S.C., manufacturing plant where Bausch and Lomb made the now-withdrawn MoistureLoc solution.

Bausch and Lomb suspended sales of MoistureLoc in Singapore and Hong Kong in February. U.S. sales were halted in April.

Hundreds of cases of Fusarium keratitis were reported and linked to the product, though it was never determined what exactly caused the problem.

F. keratitis can lead to blindness if not treated.