More than 70 firefighters responded to a call at 30 Rockefeller Center on Thursday night, clogging Sixth Avenue with fire trucks and emergency response vehicles — but there was no fire, sources said.

The massive response at the iconic high-rise building was due to a false alarm around 11 p.m. that was set off from construction work inside the building, according to fire sources.

There were no injuries and building personnel confirmed that there was no fire.