Homicide has not been ruled out as the cause of death of Teresa Casandra Robinson, the 11-year-old Manitoba First Nation girl who community members had believed was mauled by an animal.

Manitoba RCMP Chief Supt. Scott Kolody, who is in charge of criminal investigations, said an autopsy is being performed today that may "provide insight into the cause" of the child's death.

Teresa's body was found on Monday on the Garden Hill First Nation, located about 500 kilometres northeast of Winnipeg. She had been missing for a week.

Community members have said they believe she was attacked by some kind of animal, possibly a bear, but police have not backed up that theory.

"We do not have a confirmed cause of death," Kolody told reporters in Winnipeg on Wednesday.

Kolody said a number of RCMP units are in the community, including the serious and major crimes units and homicide investigators.

Teresa Robinson

The body of Teresa Cassandra Robinson, 11, was found on a Manitoba First Nation on Monday, days after she disappeared. (Facebook)

While the RCMP has not reached a conclusion on the cause of death, he would not elaborate on why homicide officers are involved in the investigation.

"This is a very difficult investigation involving that of a child and, again, we are doing everything we can with respect to covering all angles, all facets of the investigation. It's challenging, it's complex," he said.

First Nation leaders said Teresa was last seen leaving a birthday party in Garden Hill on May 5. A local search began after she didn't return home.

Kolody said RCMP were notified of Teresa's disappearance on Monday. Her body was found by a community searcher later that day.

Officers are working out a timeline to help figure out what happened, Kolody said. As well, he said officers have met with the family, First Nation members and elders.

"You just couldn't imagine what they're going through, so we're very cognizant of that and we feel that with them," he said.

In Garden Hill, hundreds of people held candles and sang in Teresa's honour at a vigil on Tuesday evening.

Official search didn't start until hours before body found

An organized search for the girl did not begin until Sunday night, according to the head of the northern chiefs' group, David Harper. 

"It's very concerning. It's concerning for everyone. So basically right now, what we're told is, we're backtracking all the information, when [were] these things reported," he said. 

Harper told CBC earlier this week he believed community members started the search for the girl Thursday.

The Manitoba Keewatinowi Okimakanak Grand Chief is acting as spokesperson for the Garden Lake community.

Harper says the girl's death has taken a toll on the community.

"It's been a heavy burden to everyone, what happened and especially watching the young children, the classmates, the families and the people, ... and the elder that last [saw] her."