Opa, recently heralded as one of the city's Top 50 restaurants by Philadelphia Magazine, has been shut tight since Jan. 18. That's when the stylish Greek taverna failed the first of three Health Department inspections in less than a week.

On Monday, a Health Department inspector returned to 13th and Sansom Streets to check  if Opa had vanquished the pests that had kept it shuttered over the weekend.

Though previously noted flies had been eradicated, evidence of mice remained. Sanitarian Gillian Clarke found mouse droppings on food containers inside a refrigerator. Citing "imminent health hazards," Clarke ordered Opa to remain closed through Wednesday.

In a statement issued Monday night, co-owners George and Vasiliki Tsiouris said private sanitation consultants they had hired had "not seen stringency from the health inspector like this before."

"These professionals have gone as far to say they'd guess no restaurant is currently as clean as Opa right now, especially after rounds of cleanings and maintenance," they said.  "[W]e are all pretty shocked by the outcome, but respect the authority of the health department and will continue to work hard to rectify this situation. We apologize for any inconvenience this may have caused our staff and guests."

The orders to cease and desist couldn't have come at a less auspicious time. Opa is one of 130 eateries participating in Center City District Restaurant Week, which launched Sunday.