Police in Honolulu are investigating an apparent quadruple murder-suicide in which a man fatally stabbed his wife and their three children before killing himself in their home over the weekend.

The identities of the victims and suspect are being withheld pending autopsies, but Lt. Deena Thoemmes with the Honolulu Police Department confirmed the juvenile victims were between the ages of 10 and 17. The ages of the adult female victim and male suspect were unknown.

Based on evidence recovered from the crime scene, authorities said they believe the father fatally stabbed his wife and their three kids before turning the knife on himself.

A motive remains under investigation.

Officers first arrived at the family's home on the island of Oahu around 8:30 a.m. Sunday, after responding to an anonymous 911 call. At the time, Lt. Thoemmes told reporters responding officers had "no one to meet them" and they did not have enough information to enter the residence. 

Officers returned approximately 45 minutes later after a "second call where they realized what happened," Thoemmes said, however she did not elaborate. 

The entire family was pronounced dead on the scene. Police said it was unclear if there was a history of domestic violence.

Chief Joe Logan confirmed Sunday's incident marked the state's worst mass killing since the 1999 Xerox murders in which 40-year-old Byran Uyesugi fatally shot seven of his coworkers.

"I would like to give my heartfelt condolences out to the families that are impacted by what happened this morning," Logan said.