Incidents of political violence have reached their highest level since the 1970s, according to a Reuters survey.

A person pretending to be a police officer assassinated a Democratic state legislator in Minnesota and killed the lawmaker’s husband in “an act of targeted political violence,” Gov. Tim Walz said Saturday. The assailant also shot and injured another Democratic lawmaker and his wife, officials said.

Representative Melissa Hortman was the top Democratic lawmaker in the Minnesota House, and a former Speaker of the House. Hortman, as well as Minnesota Sen. John Huffman, seems to have been the target of a political assassination attempt in Minneapolis.