A New York City building superintendent confronted a trespasser possibly stealing packages before he was found with a head injury and died, NYPD sources said Thursday.

Officers found the super, identified as 41-year-old Burim Havolli, at 1199 Ocean Ave., in Flatbush, Brooklyn, where a 911 caller reported an assault Wednesday morning. 

Havolli had suffered significant head trauma. He was rushed to Kings County Hospital, where he later died.

Investigators reviewed a brief cellphone video showing a person arguing with the super and acting erratically moments before the assault. 

Police said no arrests were made and Havolli's death was not ruled a homicide. Sources said a person of interest was taken into custody at the scene for questioning.

Detectives were also seen entering and exiting the building, collecting evidence and canvassing apartments to see if any residents had information about what happened.  

An autopsy later determined Havolli died from a pre-existing medical condition, police said.     

"He loved this country"

Blerim Havolli, the victim's brother, was in tears as he talked about how the two survived the Kosovo war in 1999, and escaped to America for a better life.

"He loved this country. This country helped us a lot," Blerim Havolli said.

"There's no words that can explain. This is sad. He left behind three [children] and he was only 41 years old," Petrit Havolli, a cousin, said.

The brother said the family is taking the victim's death hard.

"It's not easy to raise three kids ... 2 years old and the boy keeps asking what's going on, why is so many people here. 'Where's my father? Call him, call him,'" Blerim Havolli added.

"[He was] very caring, always there for all his tenants, very hardworking," resident Alexis Potter said.

In Burim Havolli's memory, the lobby of his building was lit up with candles and adorned with flowers, and a sign was displayed, reading, "With gratitude for all you did and sorrow for your loss."  

Package theft at the building an "ongoing problem," tenant says

A tenant also spoke highly of Burim Havolli and told CBS News New York that package theft is a problem in the building, adding there is even a sign posted to warn people about it.

"He was like your main go-to person. Something's not working, you're calling him. He was just so kind and caring," tenant Alexis Charles said.

"He was extremely professional. Everything that needed to be done, he did it," Jeff Fisher said. "This is an ongoing problem in this building, so for this to happen, like this, is truly a tragedy."

"I've seen an uptick in crime, people stealing packages, people [emboldened] and they don't care," said Gail Seton, the landlord of the building next door.

"He died protecting the building, protecting the packages of the tenants," Blerim Havolli said.

Johnny Garcia worked in the building alongside Burim Havolli for 17 years and said he considered him a brother.

"We were together every day," Garcia said. "There's no words for this happening."

The victim's family said they plan to take his remains back to his native Kosovo, where he will be buried.

Anyone with any information is asked to call the NYPD's Crime Stoppers hotline at 1-800-577-TIPS (8477), or for Spanish, 1-888-57-PISTA (74782). You can also submit a tip via their website or via DM on Twitter, @NYPDTips. All calls are kept confidential.