A tractor trailer struck and killed a woman in Brooklyn this morning, authorities said.

The victim, believed to be in her 40s, was mowed down at the corner of Church Avenue and Prospect Expressway, around 10:20 a.m., according to police and fire officials. The woman was pronounced dead at the scene.

Police and EMS are still on-scene trying to determine what caused the accident. It wasn’t immediately clear whether any criminality was suspected.

kconley@nypost.com