Four people are dead, including the gunman and his toddler daughter, following a shooting at a Brooklyn apartment this week, according to police. All of the deceased were reportedly related by blood or marriage.

As WABC reports, 27-year-old Terrance Briggs; his daughter, 1-year-old Layla Briggs; his stepfather, 57-year-old Lloyd Drain Jr.; and 15-year-old Lloyd Drain III, were found inside the home by a relative shortly after 5 a.m. Wednesday.

The New York Post reported that the toddler’s mother does not live at the location of the shooting.

There was no indication of forced entry into the residence.

Investigators say the grisly crime was likely perpetrated as a triple murder-suicide by Terrance Briggs.

The youngest victim’s grandmother reportedly found the victims in two rooms of the Brownsville apartment when she arrived to babysit.

Police describe Terrance Briggs as a suspected gang member who has an extensive criminal record.

“We do not have a motive for this incident, but we are working very hard to establish one,” said New York City Police Dept. Chief Michael Kemper.

He went on to confirm that “a firearm has been recovered inside the apartment, along with bullets and shell casings.”

Authorities have reportedly responded to numerous calls regarding domestic incidents involving Briggs, one of which resulted in a 2005 menacing charge related to allegations that he used a firearm to threaten his stepfather.

This week, loved ones are left to mourn in the wake of an act that took so many members of one family.

“It breaks my heart to see him gone and all the kids and his son, you know?” said Vanessa Swain of her friend Drain Jr. “They showed love when they can, you know, and it’s sad.”

[Featured image: Layla Briggs/Facebook]