Dawson said firearms were also found at the scene.
There was no ongoing threat to public safety, police said.
Dawson described the deaths as a tragedy.
Authorities were called to the scene at 05:15 local time (21:15 GMT on Thursday) after receiving a phone call from a "male person", Mr Dawson said.
Osmington is a collection of a few streets, farms, horse studs, vacation accommodation and vineyards supplying the premium winemaking district known as Margaret River.
Chris Paul on WCF - 'Who plays for just that?'
Despite making the playoffs and performing well during the postseason, Wade also lost in the Rookie of the Year voting to James. With James Harden sick, Paul stepped up with 41 points, 10 assists, and seven rebounds to seal a 4-1 series victory.
Lalu's son Tej Pratap gets engaged to Aishwarya Rai at glittering ceremony
Party leaders are hoping Lalu, who is lodged in jail in connection with a fodder case, will be granted bail to attend the wedding. Most of the country's top politicians, including Prime Minister Narendra Modi and chief minister Nitish Kumar, would be invited.
Alleged Israeli attack near Damascus
So, in early April , the media reported the possible involvement of the tel Aviv bombing base T-4 in HOMS. Nonetheless, the army has predicted that such an attack would not lead to a full-fledged war.
The ages of the children and adults have not been revealed. We are trying to locate other members of the family and friends.
The shooting is believed to have been a murder-suicide but this is yet to be confirmed.
"This devastating tragedy will no doubt have a lasting impact on the families concerned, the whole community".
The commissioner said the police chaplain had been called to attend the scene of the tragedy to support the emergency services. Two adults lay on the outside, and another adult and four children inside the building.
"This will be a very large scale and detailed investigation".
A local resident who did not want to be named said he understood the property belonged to the grandparents.