A University of Arizona Cancer Center researcher was stabbed and shot several times by his roommate, who then killed himself outside their midtown home Tuesday night, police said.

When police responded to the shooting call, they found 32-year-old Jadrian Rusche and 30-year-old Michael Kistner suffering from gunshot wounds in the street, said Sgt. Chris Widmer, a Tucson police spokesman.

Both men were pronounced dead at the scene, in the 4500 block of East 28th Street, near South Columbus Boulevard and East 29th Street. The shooting happened shortly after 7:30 p.m.

Based on witnesses’ statements and evidence found at the scene, police gave this account:

Homicide detectives determined the roommates began fighting in the home, and Kistner stabbed Rusche several times with a kitchen knife. Kistner then grabbed a handgun and fired several shots at Rusche, who ran out of the home and into the street.

Kistner chased Rusche and continued to fire at him.

Rusche was hit several times, police said.

Kistner then shot himself.

A neighbor of Rusche and Kistner’s said Rusche bought the red-brick house about five years ago, and four men lived at the house.

“I spoke to one of the roommates this morning who said he and a friend were in the backyard when the fight broke out in the house,” the neighbor said.

The roommate and his friend ran several houses down asking for help.

“My sister called and told me a man and a woman were trying to open the screen door, and were yelling: ‘We need help! We need

help!’ ” said another neighbor, Marco Villarreal, who was in class at Pima Community College when the incident occurred.

“My sister was frightened and closed the front door. She does not know my neighbors,” Villarreal said. “Moments later, she heard shots. I found out what happened when I got home later that night,” he said.

Rusche’s and Kistner’s bodies were lying in the street near the driveway of their neighbor’s house, Villarreal said.

Dried blood was visible on the pavement Wednesday. Rusche’s red pickup was in the driveway of his home, and the roommate’s silver Dodge Caliber SXT was parked in the street. The other two roommates’ vehicles were not at the house. The front-yard porch light remained on.

“It’s all such a shame,” Villarreal said. “I never saw a problem at their house. We would say ‘hello’ to each other often, and that was about it,” Villarreal said of Rusche.

Alfred Gallegos, a researcher at the UA Cancer Center who worked with Rusche in a previous campus research position, said all of Rusche’s co-workers were in shock.

Rusche, who was known as “Jade,” “was a nice guy who was very responsible. I knew him for about five years. He was willing to share his instruments, and he was very cooperative and willing to help out,” Gallegos said. “He was an all-around nice guy.”

Researcher Suzanne Regan said she worked alongside Rusche for one year. She said Rusche was involved in skin cancer research. He was testing drugs for treatment.

“He was very competent in what he did. He was a research specialist senior. He was a helpful person, and he never was in a bad mood,” Regan said.

Rusche began working as a researcher at the Cancer Center in May 2012 and held various research positions on campus beginning in March 2004, said Sara Hammond, a spokeswoman for the center.

He was previously a student worker on campus, starting in January 2000.

He earned his bachelor’s degree in molecular and cellular biology with a minor in religious studies in 2003, according to UA records.

Information about Kistner was not available Wednesday.

Contact reporters Veronica M. Cruz at vcruz@azstarnet.com or 573-4224 or Carmen Duarte at cduarte@azstarnet.com or 573-4104.