The first victim was found in the gutter of a quiet residential street, just as the killer was shedding blood again on the campus of a nearby community college.
Wielding some kind of sharp-edged weapon — which some reports have said was a bow and arrow — he killed a community college instructor before taking his own life in front of a classroom of students.
Police wouldn't speculate on a motive for the murder-suicide and said little about how it all developed Friday at Casper College and in a neighborhood about two miles away. They hinted, however, that the three knew each another.
Casper Police Chief Chris Walsh said an "edged weapon" was used in at least one of the killings. He didn't say more about what type of weapon it was and whether the killer used the same weapon in all of the deaths.
He said he didn't know how many students were in the class or what the topic was. The attacker wasn't believed to be a Casper College student but it appeared he knew the victims, he said.
No names were released.
"We're locating next of kin and working on notification absolutely as fast as we can," Walsh said.
The campus was locked down and class called off for the day. Later, after the lockdown, students who lived on campus trickled back to their dorm rooms.
The violence came as a shock to this typically peaceful prairie city of about 56,000 in east-central Wyoming.
"It was a little bit of a wake-up call," said freshman Nathan Hansen, of Glenrock, a town of 2,500 about 30 miles east of Casper. "It was kind of odd hearing news of that happening here."
Authorities said they didn't believe there was any further threat to the community.
All students and staff were evacuated from the classroom building where the attack occurred just before 9 a.m. MST.
The college sent out a campus-wide alert via text message and email within two minutes of receiving word of the attack at 9:06 a.m., school spokesman Rich Fujita said. The lockdown ended at about 11 a.m. after school officials received word that police were no longer searching for a suspect, Fujita said.
There are fewer classes on Fridays than any other day of the week at Casper College, so only between 1,500 and 2,000 of the college's 5,000 students were there, he added.
"It is particularly painful because of our size," Fujita said of the small, tight-knit campus.
Pearson Morgan, a freshman, was in a math class on the first floor of the science building when his instructor relayed the news in a state of shock.
"My teacher was just so sick, he said, `You can just leave,'" Morgan said.
Morgan walked outside his classroom to find a female student crying. He then turned to see two or three officers with assault rifles bounding up the stairs. Then, all the classrooms emptied and a crush of students carried him outside, but nobody panicked, Morgan said.
"There was a large group of students behind me," he said. "There was a lot of confusion."
Political science instructor Chris Henrichsen said he was showing the film "Frost/Nixon" to his Wyoming and U.S. government class when he stepped into the hall and was told a homicide had occurred on campus.
Moments later his students started getting messages about the campus lockdown on their phones.
"We locked the door and waited for further instruction," Henrichsen said.
About two miles away, Dave Larsen said he was headed to the gym when he drove past a body in a gutter with two people standing over it, one talking on a cellphone.
Larsen lives about a block from the location of the body, a well-kept middle-class neighborhood of mostly single-story houses.
Walsh said that within minutes of the initial call, there was another report of a traumatic injury about two miles southwest of campus.
The college planned a candlelight vigil and memorial service on Tuesday.
Casper College opened in 1945 as the state's first junior college and moved to its current site 10 years later. Wyoming has only one four-year university, the University of Wyoming in Laramie, which serves more than 13,000 students.
Casper is Wyoming's second-largest city. Wyoming residents refer to it as the "Oil City" because it's a hub for the state's oil industry.
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