Since then, until Friday, the country had suffered only one other mass shooting — generally defined by experts as a shooting that involves at least four victims in a singular event. But gun-control experts have been saying for years that Australia’s laws have slowly softened, and they said it was still far too common for Australians to have more than one weapon at home around children.

“Like all other jurisdictions across Australia, Western Australia’s gun laws have also been eroded as pro-gun lobby groups continue to place pressure on governments,” said Sam Lee, chairman of Gun Control Australia. “From a gun regulation perspective, this horrific shooting raises many concerns about access to firearms, particularly on rural properties.”

Among the ways the regulations in Western Australia have been eroded, critics say: No police checks are required to obtain second or subsequent hunting rifles; firearms safety-training courses are not required; there is no minimum age to obtain a minor’s permit; and there is no limit on the quantity of ammunition that can be purchased at any given time.

In Osmington and in Margaret River, though, there was little interest in political debates. There was only grief and shock.

About a dozen people were gathered at a support center on Saturday afternoon, established by the local government to provide counseling to residents. Some sat outside in the sunshine, talking quietly with one another, while others spoke with professional counselors. Elsewhere in the town, local people seemed stunned, while tourists milled around — providing a stark contrast.

Adam Navarone, who recently moved to Margaret River, where he works at a small shop, said his younger cousin had played football with one of the young victims.