NYPD Identifies Family Stabbed to Death in Murder-Suicide — Including 2 Toddlers and 'Loving and Devoted' Mom

New York City police have identified four family members who were found dead in an apparent murder-suicide at their Upper West Side apartment earlier this week.

The NYPD confirmed to PEOPLE that Edison Lopez, 41, Aleksandra “Ola” Witek, 40, and their two sons, Lucian, 3, and Calvin, 1, were found stabbed to death inside the family’s apartment on Monday afternoon.

A NYPD spokesperson told PEOPLE that Edison and Ola, his fiancé, according to a GoFundMe, were found dead with stab wounds to the neck. Lucian had stab wounds to his torso, and Calvin, the youngest son, was found dead with stab wounds “around the body,” police said.

All four were pronounced dead at the scene, while their family members have told media outlets they believe the unexpected killings happened a day earlier.

“The investigation remains ongoing at this time,” police said.

The gruesome scene was reportedly first discovered on Monday by Lopez’s father Mario and Witek’s brother Lukas, who attempted to drill through the family’s apartment door after not hearing from the family in a day, according to the New York Post. After the two men saw blood through the door, the family members called police who soon arrived on scene and discovered the four bodies.

“We saw them inside,” Mario Lopez, Edison’s 66-year-old father, told Gothamist over the phone this week. “They were already dead, whatever happened, happened maybe the day before.”

Mario said there were no signs of trouble with his son’s family.

“If you look around and ask their friends – very levelheaded individuals. Both of them,” he told the outlet about Edison and Ola. “You usually see problems in a couple where you see the behavior of the children affected immediately. Their grandmother, my wife, took care of them. We didn’t see anything.”

Neighbor Jeff Kimmel told NBC New York he’d known the Lopez family for more than two decades and “always thought they were really nice.” Another neighbor told the news station Edison was “always with his kids” and seemed friendly.

Edison grew up in the apartment and took over as the building’s superintendent from his father, according to ABC News.

Ola was a preschool teacher and “a proud Polish mom,” her family said in a GoFundMe launched Tuesday.

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“Ola was an incredibly loving and devoted stay-at-home mom to her two young sons,” the family said. “Being a NYC school teacher, she instilled her knowledge and teachings on the growth of her boys who had blossoming imaginations and whose curiosity and sweetness to family and friends alike captured everyone’s hearts.”

The family added: “A proud Polish mom, Ola shared her culture and language and made the lives of her boys bright and full. Her boys loved playing with their toys, story time with mom, and were two delightful babies to all that loved them.”

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.