Autopsy results released Wednesday determined that James Easton Kelly killed English professor John Locke on Monday and then shot himself in the heart.
A receipt for a 50-round box of ammunition was discovered Wednesday in Kelly's rental car, parked near the English department's offices.
The receipt was stamped 11:27 a.m. by a Wal-Mart 10 miles from the Fayetteville campus. Police were summoned to Kimpel Hall at 12:14 p.m.
"He went immediately to campus," university police Chief Larry Slamons said.
Slamons said the bullets purchased at that Wal-Mart were the same one used in Kelly's .38-caliber revolver and the same bullets that killed Locke. An attaché case found in the office contained the rest of the bullets and 46 additional rounds, he said.
He wouldn't say whether other professors could have been targets.
"I cannot speculate at this time about the other professors," Slamons said. "He had the ammunition. In the event he had left that building, it would have been available to him."
According to the car rental records, Kelly rented the car on Aug. 21, the same day he was notified of the graduate school's decision to dismiss him. Kelly had been taking graduate classes at the university for 10 years.
Locke, Kelly's advisor, was also chairman of the committee that voted to deny his reinstatement to the comparative literature program. Locke abstained from the vote, but he likely was the one who notified Kelly of the decision, Slamons said.
"He was the most visible and he was giving him the bad news," he said.
Monday's meeting between Locke and Kelly wasn't listed in the professor's appointment book, and Locke had previously told a colleague that he was apprehensive about meeting with Kelly in private.
In the attaché case found after the shootings, police discovered five letters addressed to Kelly including the one telling him he could no longer take classes for credit toward an advanced degree.
English professor Brian Wilkie said Kelly had been dismissed from the graduate program because he was not making satisfactory progress toward his doctorate.
The university said Kelly had enrolled in, then dropped, English department classes several times over the past three years. He was enrolled as a non-degree student for the fall semester.
After the first shot rang out in Kimpel Hall on Monday, graduate student Bethany Edstrom said she heard someone say: "I didn't do anything." Slamons said the shot through Locke's hand indicated he raised his arm in a futile attempt to defend himself, Slamons said.
Officers responding to at least three 911 calls said a man behind Locke's office door said he had been hurt but tat they shouldn't enter. Slamons said the Locke and Kelly may have struggled, with Locke perhaps landing a blow before being fatally wounded.
Moments later, they heard Kelly kill himself with the final of four shots. Two bullets remained in the revolver when officers finally entered the cluttered office, Slamons said.
Police said Kelly had no criminal record and there was no indication of discipline problems on his university record.