04/07/2015 01:34 EDT | Updated 06/07/2015 05:59 EDT

Don Dunphy aimed loaded rifle at cop prior to fatal shooting: RCMP

Don Dunphy, who was shot and killed by a member of Newfoundland and Labrador Premier Paul Davis's security detail, aimed a loaded shotgun at the officer prior to being fatally shot Sunday afternoon, the RCMP says.

According to the Mounties, the Royal Newfoundland Constabulary officer was invited into Dunphy's home when he arrived last weekend in Mitchells Brook, N.L., to investigate what was perceived to be a threat made against the premier and another politician.

A 15-minute conversation occurred when there was a "sudden and dramatic" change in the demeanour of the visit, the RCMP said in a statement Tuesday.

At that point, the RCMP said, Dunphy aimed a long-barrel firearm at the officer.

The RCMP said evidence indicates the RNC officer responded with lethal force. Dunphy died at the scene.

A .22-calibre rifle was found on the floor of Dunphy's home. During a forensic investigation, it was determined the gun was loaded.

According to the RCMP, the RNC officer conducted a routine "risk assessment" before making the trip to Mitchells Brook to investigate the perceived threat made against Davis and MHA Sandy Collins.

However, the officer determined it was a "low-risk" situation and it wasn't necessary to bring along a second officer. The RCMP Holyrood detachment, which polices the rural area, was contacted prior to the visit.

The RCMP said its investigation is ongoing.