A knife-wielding man made his way into a pregnant woman's Queens apartment building early Sunday morning, dragging her down three flights of stairs before stabbing her to death in the lobby. The attacker quickly ran, leaving dying woman lying in a pool of blood.

Police have identified the victim as Jennifer Irigoyen, a 35-year-old real estate agent and fitness instructor who was reportedly five months pregnant at the time of her death. Around 1 a.m., officers responded to a 911 call from one of Irigoyen's neighbors at 60-80 Myrtle Avenue in Ridgewood.

Maurice Roman Zereoue told the NY Post he heard her scream during the attack—"He's got a knife! He's going to kill the baby!" Zereoue reportedly looked out into the hallway and saw Irigoyen's "hands hanging on" to a wall as she tried to keep a man in a hoodie from pulling her down the stairs. Another neighbor confirmed that she had also heard arguing, and Irigoyen "yelling ... about wanting to protect her baby."

While Zereoue's girlfriend called the authorities, he ran down to the vestibule and found Irigoyen still alive, with stab wounds to her neck and stomach. "She was at the bottom of the stairs bleeding out," he told the Post. "She had a little dog with her, a pug, I think. Its feet were soaked in blood." He said he asked her if she knew her attacker, "And she kept nodding yes and waving her arm," unable to speak as her throat filled with blood.

Responders rushed Iriogyen to Wyckoff Hospital, where she and her baby both died. After reviewing security footage from the attack, Irigoyen's super, Lisa Ramos, told the Post that the killer landed his first blow on her stomach.

"I had a tenant that heard what was going on. She thought it was a party, because they have parties all the time," Ramos told the NY Daily News, calling Irigoyen a "beautiful person," "bubbly," and "warm." She had lived in her third-floor apartment for about a year, and had a young son (alternately reported as 12 and eight years old) whose grandmother has since taken him in.

The killer left bloody boot tracks in his wake as he fled the building, running east on Myrtle toward Fresh Pond Road. No arrests have been made, but police are reportedly searching for Irigoyen's boyfriend: One NYPD source told the Post that he has not come forward to ask for any information about the murder. We will update as more information becomes available.