Investigation into the online activity of Chapel Hill shooting suspect Craig Hicks has revealed that though he regularly condemned religion, he also apparently promoted freedom of belief.

He supported the proposed construction of a mosque near Ground Zero in New York. AP found a 2012 Facebook post in which Hicks said: "I hate Islam just as much as Christianity, but they have the right to worship in this country just as much as any others do".

The latest findings have called into question whether his crime was religiously motivated.

The 46-year-old has been charged with the murder of three young Muslims in North Carolina on February 10.

His victims have been identified as Deah Shaddy Barakat, 23, his wife Yusor Mohammad Abu-Salha, 21, and her sister Razan Modammad Abu-Salha, 19.

Gunshots were heard at their home in an apartment complex at the University of North Carolina, Chapel Hill, at around 5.15 pm on February 10. All three were pronounced dead at the scene, with sources saying they had been shot in the head.

A Facebook page under Hicks' name describes him as an "anti-theist", with Hicks using the page to criticise religion. He regularly posted images with text mocking religious beliefs.

One post, from January 28, reads: "People say nothing can solve the Middle East problem, not mediation, not arms, not financial aid. I say there is something. Atheism."

Another says: "I have no need for religion. I have a conscience."

He has also quoted Elton John's declaration that he would ban religion completely: "The reality is that organized religion doesn't seem to work. It turns people into hateful lemmings and it's not really compassionate."

Police have pledged to investigate whether last week's murders were motivated by religion, as has been speculated.

Hicks' wife, Karen, who is now filing for divorce told a news conference on Wednesday that the killings "had nothing do with religion or the victims' faith".

Her husband had been engaged in a long-standing dispute over parking with the victims. Hicks believed "everyone is equal" and "championed the rights of others", she said.