The recent shootings of lawmakers in Minnesota are part of a disturbing trend toward politically linked violence, ABC News analysts say.

U.S. Capitol Police increased security for Klobuchar and Smith following the attacks, which occurred early Saturday morning. Minnesota's entire congressional delegation, both Republicans and Democrats, released a joint statement condemning the killings.

Vance Boelter has been charged in the shootings of two Minnesota lawmakers and their spouses. Boelter, 57, is charged with two counts of second-degree murder and two counts of second-degree attempted murder, according to the criminal complaint filed in Hennepin County Court on Saturday.

The suspect wanted in the slaying of a Minnesota lawmaker and her husband, as well as in the injury shooting of a state senator and his wife, was found Sunday night armed and crawling in a field in a sparsely populated stretch of Minnesota,

State Senator John Hoffman and his wife, Yvette, were gunned down at their home early on Saturday morning, but survived. Melissa Hortman - the top Democratic legislator in the state House - and her husband, Mark, were shot and killed. Yvette Hoffman said in a statement that she and her husband John were "devastated" by the Hortmans' deaths.

The names of some congressional officials from the state were listed in the suspected shooter’s papers.

"Hi everyone! I’m looking to get back into the U.S. Food Industry and I'm pretty open to positions," Boelter wrote on LinkedIn last month.