PICTURED: Chicago couple and two sons shot dead along with their three dogs in mysterious massacre – as cops hunt gunman and the victim’s sister pleads for ‘answers’ about ‘horrific crime’

The family of four who were slaughtered along with their three dogs in their Illinois home have been pictured for the first time as police continue their hunt for the killer.

Zoraida Bartolomei, 32, her husband Alberto Rolon, and their children Adriel, 10, and Diego, seven, were shot Sunday in their family bungalow in Chicago.

Romeoville Police investigators have ruled out a murder-suicide and warned the killer is still on the loose.

Their family said they have no idea why anyone would want to kill them, and Zoraida’s devastated sister has made a plea for answers.

Bryana Bartolomei shared a photo of the family on Facebook, saying, “I want to know what happened to my cousins, my sister and her husband, and WHY?

Romeoville Police investigators have ruled out a murder-suicide and warned the killer is still on the loose

Zoraida’s mother Lydia, from Puerto Rico, previously told DailyMail.com that they were “so happy” and that they had just purchased their $250,000 home in Romeoville five months ago

“They were shot dead in their home.” In the photo, Zoraida and Alberto can be seen beaming with their two sons, one of whom playfully holds a lock of his mother’s hair.

A fundraiser was set up on Monday to help cover funeral costs, with their children described as ‘the sweetest and innocent angels’.

Friends describe them as “hard-working people who just bought their first house.”

“Their children were the sweetest and innocent angels who could take your worries away,” the fundraiser says.

‘In just a few hours, their lives, the lives of their families, changed completely. Without them the world will be a much bleaker place.”

They called on anyone with information about the shooter to contact police.

Zoraida’s mother Lydia, from Puerto Rico, previously told DailyMail.com that they were “so happy” and had bought their $250,000 Romeoville home just five months ago.

Zoraida Bartolomei, 32, her husband Alberto Rolon, and their children Adriel, 10, and Diego, seven, were gunned down by a mysterious gunman on Sunday in their cozy family bungalow on Concord Avenue in suburban Chicago.

Romeoville police found the murdered family after they were asked to conduct a welfare check when one parent didn’t show up for work at 6 a.m. Sunday and no one answered the landline.

She last spoke to her daughter shortly before her death over the weekend, as the family settled down to watch a movie, and she couldn’t understand why they were being targeted.

Romeoville police found the murdered family after they were asked to conduct a welfare check when one parent failed to show up for work at 6 a.m. on Sunday.

Officers were confronted with carnage when they arrived at 8:40 PM that evening.

The family appears to have moved to the US in recent years, possibly from Puerto Rico, where Zoraida’s mother is based.

Zoraida was a certified beautician, while her husband’s age and profession are unknown.

Chris Burne, deputy chief of the Romeoville Police Department, revealed few details during a news conference Monday, citing the “sensitivity of the case and the need to protect the integrity of the investigation.”

But he was convinced that none of the dead were responsible and that the gunman left the scene.

A fundraiser was set up on Monday to help cover funeral costs and raise awareness of their cause, describing their children as ‘the sweetest and innocent angels’

“Due to the time that has passed, more than 18 hours from the time we were contacted, we are not asking anyone to provide shelter,” he added.

‘We are not actively looking for anyone in the area, but we always ask our residents to be self-aware and report anything they consider suspicious.’

Police believe the murders took place in suburban Chicago between 9:00 PM on Saturday, September 16 and 5:00 AM on Sunday.

Crime scene technicians removed several brown and pink bags along with part of a window from the three-bedroom house as the investigation began yesterday.