Workers began installing temporary supports Tuesday evening to stabilize a Manhattan high-rise after structural problems forced the evacuation of the building and several surrounding properties, though city officials warned that the situation remained serious despite signs the structure had stopped shifting.

The 37-story building at 235 E. 42nd Street, the former global headquarters of Pfizer, had been undergoing conversion into more than 1,600 apartments when construction workers discovered buckling steel columns and sagging floors Tuesday morning. Officials said the workers immediately evacuated the building, prompting a broader emergency response in the busy Midtown corridor near Grand Central Terminal.