Two weeks before police said Joshua Mendel gunned down sophomore Nicole Schiffman and her childhood friend Carol Kestenbaum in Tempe, Ariz., on Sunday and turned the gun on himself, Mendel sought help from police.

Mendel, 22, called Tempe police Feb. 4, requesting help for his alcoholism and asking for the contact information of alcohol treatment centers. He didn’t seem quite stable, but the officer that responded to the call included in her report that “he did not feel like he wanted to hurt himself in any way,” said Tempe police spokesman Sgt. Mike Horn.

The officer offered him a few phone numbers where he could reach help and left without any indications that Mendel might resort to violence. But those who knew Mendel said in interviews that in the weeks prior to the murder, Mendel had grown increasingly tense about his relationship with his girlfriend Alexandra Wake, 18, a relationship Kestenbaum openly disapproved of.

He had a tendency to be to be possessive, said Megan Racobaldo, an Arizona State University student who lived with both Kestenbaum and Wake last year. Mendel was often overbearing with Wake and never seemed completely together, Racobaldo said.

“It was just an obsession,” she said. “The last month had just been a roller coaster with those two.”

But no one expected him to show up at Kestenbaum’s off-campus Tempe apartment with two loaded pistols, hiding until Schiffman and Kestenbaum arrived home. When they did, he emerged and fired on Kestenbaum, killing her instantly. Schiffman was shot as she attempted to run and died at a Phoenix hospital just over an hour later.

Mendel called Racobaldo four times that morning, and just eight minutes before a neighbor placed the first calls to 911, he left an obscure message on her machine, which Racobaldo said was “completely irrelevant to what was about to happen.”

Racobaldo had planned to go out with the two girls that night, but decided to stay in because she was tired after the past two days of celebration. Detectives told Racobaldo she was lucky to be alive.

Police believe Mendel was angry over Kestenbaum’s outspoken disapproval of his relationship with Wake, and his sister told Newsday that Mendel had openly spoken about suicide.

“He promised my mom he was going to get help and wouldn’t do anything,” his sister, Carrie Mendel, 23, of Davenport, Iowa told reporters. “I know those girls’ families have to be hurting so bad. But this wasn’t Josh.”

Police said Mendel had no previous criminal records in Arizona or Illinois and said toxicology exams on his body began Monday. A Maricopa Medical Center spokesman in Tempe said results wouldn’t be available for another two weeks.

Friends said Mendel and Kestenbaum had known each other since attending high school together in St. Charles, Ill., and at first Racobaldo said the relationship seemed to be working. Although he never showed any signs of the violence he committed over the weekend, as the relationship progressed, Racobaldo said Wake would often approach her friends with complaints.

Kestenbaum tried to take a stand and refused to be around Mendel.

“What she most cared about was her friends. All she ever meant to do was look out for the best friend of Alex,” Racobaldo said. Now, Wake is so distraught, “she can’t even understand what she’s saying half the time,” Racobaldo said.

Ron Schiffman, Nicole’s father, said from his home in Merrick, N.Y., that he was concerned that the man who murdered his daughter never received any counseling, even though he apparently knew he had a problem.

“All we want to do is find out how this kid was allowed to kill my daughter,” Schiffman said. “He called the police weeks before and nobody helped him. So what did he do?”

Contact reporter Ben Slivnick at slivnickdbk@gmail.com.