Melissa Klein

City Councilman Ben Kallos, who represents the area, said the Blood Center has not been transparent about the lab.

“I hate to think of what they’re cooking up in there,” he said.

The Blood Center told The Post the lab will be for its use only and “is a necessary component for the research and development of new antivirals and vaccines.” It said it has used the lab for hepatitis and HIV research in the past.

The Blood Center has tried unsuccessfully for a rezoning and expansion several times, Kallos said.

In-person learning is now supposed to start Sept. 29 for those in kindergarten through fifth grade and to Oct. 1 for older students after de Blasio made an 11th-hour decision to delay the opening.

Councilmen Ben Kallos, who joined Councilman Brad Lander in July saying the program fell far short of the number of slots needed, said the city had done a poor job of explaining exactly what Learning Bridges provided and how to apply.

“I would just say it’s a total mess,” Kallos said.

City Hall could not provide much in the way of answers including how many children had been offered slots.

"The city does not limit how long a sidewalk shed can stay in place. Councilman Ben Kallos (D-Manhattan) has proposed legislation that would require such eyesore sheds be removed after seven days if no work takes place, but the bill has stalled."