NEW YORK —  The city health department was trying to figure out Sunday why a KFC-Taco Bell restaurant had passed an inspection the day before video footage caught a dozen rats scampering across its floors.

"It doesn't look like the inspection that was done Thursday met our standards," said Geoffrey Cowley, a health department spokesman. "I don't want to prejudge that. We're concerned and we're going to carefully revaluate that inspection."

The fast-food operation, located in Greenwich Village, was shut down by the city on Friday after the video of the rodents was widely broadcast and attracted streams of sidewalk gawkers. It remained closed on Sunday.

A failing inspection score issued by the health department is 28 or above.

The restaurant passed an inspection in March 2006 — though it was fined $1,300 for some violations including mice droppings — earning 23 points. On Thursday, the KFC-Taco Bell passed another check — earning nine points — after complaints to the city's information hotline prompted an inspector to visit.

On Friday, however, a more senior inspector gave the restaurant 92 points in violations, Cowley said.

Yum Brands (YUM), the parent company of KFC-Taco Bell, has called the situation unacceptable and a violation of its high standards. The company said construction in the basement of the building apparently stirred up the rats.

Cowley said no action had been taken against the Thursday inspector but that the department is looking carefully at the situation. "We inspect 30,000 food establishments every year," he said. "We're doing vigorous enforcement."