US President Barack Obama has denounced the killing of three Muslim students in Chapel Hill, North Carolina as "brutal and outrageous murders," the BBC reported on Friday.
In a statement, Obama said no one in the US should be targeted for "what they look like" or "how they worship".
With a suspect in custody, police are still investigating the motive, amid family claims it was a hate crime.
The FBI has opened an inquiry into the case.
Deah Shaddy Barakat, his wife Yusor Mohammad Abu-Salha and her sister Razan Mohammad Abu-Salha were found dead on Tuesday evening in their home near the University of North Carolina, where Barakat was a dental student.
Craig Hicks, a neighbour of the students, has been charged with the murders. Hicks' Facebook profile included a photo that read "Atheists for Equality". He also frequently posted quotes critical of religion.
Obama called the murders "brutal and outrageous" and said the FBI would be investigating whether any "federal laws were violated".
"Michelle and I offer our condolences to the victims' loved ones," he said.
"As we saw with the overwhelming presence at the funeral of these young Americans, we are all one American family."