HUNTINGTON BEACH — Despondency over a recent surgical complication may have caused a man to shoot his next-door neighbor to death, Friday, Dec. 15, and then kill himself, according to his sister.

Janet Englehardt of Tustin said Friday night that her brother, Michael Busenburg, 78, had been in a lot of pain following a medical procedure on his intestines.

“He didn’t set out to kill,” she said while sitting in a white SUV parked next to yellow crime scene tape that blocked the entrance to the condominium complex where Busenburg lived. “It happened in the moment.”

Authorities as of Friday night had not officially identified the two people who were killed. Family and friends identified the other person slain in the apparent murder-suicide as 62-year-old Liz Noriega.

Busenburg and Noriega lived next to each other in the 4100 block of Aladdin Drive in the Huntington Harbour Marina area.

Around 8:07 a.m., Huntington Beach officers found a man and woman outside of the condo complex with gunshot wounds. A weapon was also found at the scene.

Police have said the pair had an ongoing dispute, but did not elaborate further on a possible motive.

The location of the shooting remained an active crime scene Friday night. Detectives could be seen walking in and out of the condo complex.

At the time of the shooting Busenburg, an unmarried, retired photographer, was on the phone with a friend in Michigan, Englehardt said. She added the friend heard the shots ring out over the phone and quickly contacted her.

Claria Lincoln of Palm Springs, a long-time friend of Busenburg, said while he and Noriega “picked at each other,” she was unaware of any serious problems that could have led to the shooting. She described Busenburg as “quite a character” who was well known in the Huntington Harbour area.

“Michael Busenburg and Liz Noriega will be greatly missed,” she said on behalf of Busenburg’s family. “We would like to extend our prayers as well to those harmed by today’s incident.”

Noriega’s family and friends said they are also shocked by the shootings.

“She is not someone to be involved in a murder-suicide, said Jeanne Dieteren of Hemet, Noriega’s sister. “She was very caring and giving. It’s a tragedy.”

Noriega was employed as a Realtor at RE/MAX Terrasol in Huntington Beach.

“All her clients loved her and had nothing but wonderful things to say about her,” Leo Betancourt, owner of the brokerage where Noriega worked.