Four young adults from Minnesota have been found dead in an abandoned SUV in a Wisconsin cornfield, police said, a quadruple homicide case that has more questions than answers now and has left families shattered.

The victims, friends from the Twin Cities area, were probably driven to the small town of Sheridan, Wis., where they were found on Sunday, Dunn County Sheriff Kevin Bygd said at a Tuesday news conference. Autopsies performed Monday found that all died of gunshot wounds, police said.

"Obviously we've had homicides in the last several years," Bygd told reporters, "but something of this magnitude . . . this is a first."

Three victims from St. Paul were identified as Jasmine Christine Sturm, 30; Matthew Isiah Pettus, 26; and Loyace Foreman III. The fourth was Nitosha Lee Flug-Presley, 30, of Stillwater, Minn.

Sturm, Pettus' half sister, was in a relationship with Foreman, and was close friends with Flug-Presley.

Days later, police are still grappling with a case in which few details are known.

"This is a coldblooded tragedy," Damone Presley, the father of Flug-Presley, told The Washington Post. "They killed my daughter."

The Wisconsin sheriff's office said there was "a high degree of certainty" that the suspect or suspects were no longer in the area, located about 70 miles outside St. Paul, Minn. Police believe those involved had no connection to the Sheridan area "other than perhaps randomly driving out of the Twin Cities," Bygd said.

"We do not know a motive yet," he said, calling it "a mystery." "Everybody's a suspect at this point."

Jessica Foreman, the mother of Loyace Foreman III, told The Post she last spoke to her son on Thursday about an annual family trip to an apple orchard. Foreman said her only son was "a devoted father" to his two children, ages 7 and 13, and "a protective big brother and the best uncle ever." He was also "an immensely talented artist."

"He was in love and looking forward to a future with Jasmine Sturm," she said in a text message.

Presley described Flug-Presley as a doting mother of two children, ages 4 and 10.

He said she had asked if he could watch one of her children while she went out with friends on Saturday night. Presley last spoke to Flug-Presley around 8:30 or 9 p.m. Saturday, when she called to ask if he was on his way. She left before he arrived, he said. He said she and her friends had planned to go to Shamrocks, a bar and restaurant in St. Paul where Sturm and Pettus worked, and at least one other bar that night.

But she never came home, he said. Text messages went unread and calls were going straight to voice mail. He grew worried when he couldn't get in touch with his daughter the next day, and the family contacted authorities. Relatives of the other victims also became concerned, noting it wasn't like them not to return messages.

At 2:18 p.m. Sunday, the Dunn County Sheriff's Office received a 911 call from a farmer in the area about "people in a vehicle that were not moving," Bygd said. About 12 minutes later, authorities found a black SUV with Minnesota license plates parked in a field of tall cornstalks.

Presley said he was notified early Monday that four bodies had been found in an abandoned vehicle in Wisconsin.

"I was bewildered because she doesn't know anybody in Wisconsin. The first thing I said was, 'Wisconsin? Are you sure?' " he told The Post. "That's when we started assuming that something tragic had happened to her."

Bygd said the four people were probably killed less than 24 hours before the vehicle was found, but authorities remain uncertain of the exact time.

A second dark-colored SUV may have been traveling with the black SUV that was found with the victims inside, police said in a news release. The abandoned SUV was captured on surveillance video at a gas station at around noon on Sunday, two hours before it was discovered in the cornfield, according to the Star Tribune.

The Dunn County Sheriff's Office is being assisted in the investigation by several state agencies, including the Wisconsin Division of Criminal Investigation, the Wisconsin State Patrol and the Wisconsin Department of Justice's crime lab. Investigators are reviewing security footage and traffic cameras for any information to help piece together the quadruple homicide case.

"Our hearts go out to the family and friends of these victims," Bygd said. "I wish we could release more details of our investigation, but we have to balance the public's desire to know the details with running the risk of harming our investigation."

At Shamrocks, friends are mourning the loss of the group, including their co-workers, Sturm and Pettus. Mike Runyon, co-owner of the bar and restaurant, told The Post that the business was processing "the loss of these two people we dealt with on a daily basis." He remembered Sturm, who was also an office assistant at a law firm, as an adoring mother.

"We are at a loss for words and are still in a state of shock over what's happened," he said. "It's just a very somber moment. We're grieving with the families."

Presley is pleading for anyone who knows anything about the death of his daughter and her three friends in the "heinous, deliberate crime" to come forward.

"Sometimes innocent people pay a penalty, but the innocence of my daughter and the other three individuals who were killed should not be overlooked," he said. "There was no need to take my daughter's life - no reason at all."