Police are calling the shooting death of a 52-year-old woman a "calculated" slaying and have arrested four people - including the woman's 20-year-old son.
Nancy Lynn Everson was killed early Sunday and police arrested her 20-year-old son, Grant Everson, a few hours later. Police Chief Scott Knight said Monday that three other suspects also were arrested.
The killing was "planned in advance, very calculated and coldly carried out," Knight said.
Detectives executed a search warrant at a home in Burnsville and recovered a "significant" amount of evidence, including what they believe is the murder weapon, Knight said. Besides Grant Everson, two adult males and one juvenile male were arrested.
In a news release Monday night, police said they believe the motive was money Grant Everson expected to receive after the death of his parents.
Police also asked for the public's help in finding a plastic black shotgun case, possibly filled with dark clothing, gloves and tennis shoes. They believe the case was placed in a commercial dumpster between Interstate 494 and Highway 62. Police were also looking for dark clothing placed near or in the Minnesota River near Jordan.