(CNN) -- The man accused of gunning down seven people at a California religious college from which he was expelled will be arraigned Wednesday.
One L. Goh, 43, sat in an Alameda County jail early Wednesday morning, booked on charges of murder and kidnapping.
Authorities said Goh was upset he had been expelled from Oikos University, a small college in Oakland that caters primarily to the Korean-American Christian community.
On Monday morning, he walked into the single-story building, took a secretary hostage and went looking for a particular female administrator, Oakland Police Chief Howard Jordan said.
Realizing the administrator was not in the classroom where he'd hoped to find her, Goh shot the secretary and ordered the students to line up against the wall, police said.
Not all of them cooperated, Jordan said, and so he began shooting.
"I'm going to kill you all," the gunman allegedly said.
"This was a calculated, cold-blooded execution in the classroom," the police chief said. The suspect "just felt a certain urge to inflict pain on them."
The first 911 calls came in at 10:33 a.m.
"Shots coming from inside the building, people are running out screaming," a dispatcher says in one of the police radio exchanges.
After the shooting, the gunman left the classroom, reloaded his semiautomatic weapon and returned, firing into several classrooms, Jordan said.
He ended his rampage by driving off in a victim's car, police said.
In all, seven people were killed and three were wounded.
The victims, six women and one man, ranged in age from 21 to 40 -- and hailed from countries including Korea, Nepal, Nigeria and the Philippines.
With the exception of the secretary, all of them were students.
"This happened within minutes," Jordan said. "We don't think the victims had any opportunity to resist, any opportunity to surrender."
Police arrived at the college to find a chaotic scene.
"There's a female bleeding down on the ground, face down on the concrete," a dispatcher says in one radio exchange.
Inside the building, survivors hid behind locked doors or desks.
"They were just pulling out bodies after bodies," Art Richards, a witness said.
The suspect was arrested about an hour later, when he surrendered to police at a grocery store in the Oakland suburb of Alameda, Jordan said.
Goh offered no resistance when arrested, Jordan said, and was "very cooperative, very matter-of-fact, very calm."
"He planned this several weeks in advance," Jordan told KTVU on Tuesday. "He was so upset he went out and purchased a weapon and had every intent to kill people yesterday."
Investigators have determined that the gun was obtained legally in California, but they have yet to locate it.
On Tuesday night, mourners packed church pews at a memorial service in Oakland for the victims.
"We realize that at this time we have to draw together, uniting for peace, praying for peace in our city, and praying to stop the violence," said a woman who introduced various parts of the service.
Police said Goh was self-conscious of his inability to speak English like a native and felt that students and others at the school made fun of him, police said.
It wasn't immediately clear why Goh had been expelled from the college but "we've been told that some of the possibilities are that he was expelled for his behavioral problems, anger management, but nothing specific," Jordan said.
While Goh appeared close to his family, visiting his parents in senior housing, he struggled personally with significant debt -- including a tax lien by the Internal Revenue Service, according to court records.
CNN affiliate KGO said Goh's brother, a staff sergeant in the Army, died in a car accident while training with the Speical Forces.
CNN's Michael Martinez, Sara Weisfeldt, Matt Smith, Alan Duke, Paul Vercammen, Dan Simon, Ashley Hayes, Catherine Shoichet and Augie Martin contributed to this report.