A woman has been charged with assault after an argument over a child’s sandcastle erupted at a primary school playground in Perth’s western suburbs.

The mother of a child at Dalkeith Primary School has been accused of slapping another parent when a verbal dispute allegedly turned physical last month.

Wembley acting Sen. Sgt Ryan White said the incident was sparked when the child of the accused woman damaged a sandcastle built by another child.

He said an argument broke out between the mothers of the children. Another woman was allegedly struck when she stepped in to defuse the situation.

In a statement, police said they would allege that a woman “became aggressive” towards another woman after a verbal altercation at the end of the school day.

“It will be further alleged the victim, a woman in her 30s, saw this and positioned herself in between the two,” the statement said. “The victim looked away and the woman struck her on the neck.”

An Education Department spokeswoman confirmed there was an incident between two adults on March 14.

A 41-year-old Dalkeith woman will appear in Perth Magistrate’s Court on May 24.

Principals Federation of WA president Bevan Ripp said the incident was another example of the difficulties that principals faced in managing parent behaviour in schools.

“Any behaviour of that sort by adults on a school site needs to be dealt with firmly,” he said.

“Kids shouldn’t be subjected to witnessing that sort of behaviour when they’re just going to school to learn.”

WA Primary Principals Association president Ian Anderson said school violence could happen anywhere, no matter the post code.