"What this individual allegedly did is what abusive individuals have done for decades," one expert said.

Vance Boelter is suspected of shooting two members of the state legislature and their spouses on Saturday – and may have had more bloodshed in mind.

"What this individual allegedly did is what abusive individuals have done for decades," one expert said.

After shooting two local politicians, Vance Boelter texted his wife "prepare for war", say investigators.