Eight children, ranging between the ages of 18 months and 15 years old, were found murdered in their home in the northern Australian city of Cairns on Friday, the Sydney Morning Herald reported. Returning from the store, the children's 20-year-old brother discovered his siblings along with his mother, who had also been attacked but was the only one alive.

"They're only babies," Lisa Thaiday, a relative, told CNN.

Australian media reportedly said at least some of the victims had been stabbed, but local authorities declined to confirm the reports ahead of autopsy reports.

Upon discovering the scene, the brother called police, who rushed his 34-year-old mother to the hospital, police said. She had suffered serious injuries to her torso and her neck but was able to assist Queensland authorities with their inquiries.

Police and emergency services blocked off streets in the neighborhood where the apparent mass murder occurred; they labeled it as one of the worst crime scenes the northeastern Australian state has seen in recent memory.

"During an examination of the residence, police located the bodies of the children, all aged between 18 months and 15 years," the Queensland Police Service said.

Police have yet to name any formal suspects in the case, but Detective Inspector Bruno Asnicar said people in the neighborhood need not worry about imminent danger.

"There's no need for the public to be concerned about this, other than it's a tragic, tragic event," Asnicar said.

The detective said the area is under control, and police are "looking at anybody who's had any involvement."

"These events are extremely distressing for everyone," Asnicar said. "Police officers aren't immune from that. We're human beings as well."

Neighbors, friends and family of the children laid flowers, lit candles and prayed at the site of the crime, the Australian noted.

The country's prime minister, Tony Abbott, called the killings "an unspeakable crime."