Police are investigating a brutal attack on a woman in Brooklyn.

The NYPD is looking for Yong Lu.

Investigators say he stabbed his girlfriend repeatedly with a steak knife Thursday afternoon.

The woman's right arm was severed, along with two fingers on her left hand.

It happened inside the couple's home located at 523 55th Street in Sunset Park.

The victim was brought to Bellevue Hospital in critical condition.

Anyone with information on the case should contact the Crime Stoppers hotline at 1-800-577-8477, or text CRIMES and then enter TIP577, or visit www.nypdcrimestoppers.com.