In his application for the order, which a Santa Clara County judge granted, Jingjiu Wang wrote that Mr. Zhao had crept into his room at their shared San Jose apartment in March 2013 and demanded his paycheck. When Mr. Wang was unable to produce it, he said, “Mr. Zhao said to me, today I am going to kill you,” and then attacked him, trying to smother him with a pillow. Two days later, he said, Mr. Zhao warned him that “bad things could happen” and threatened to bury a kitchen knife in his skull if he did not help him get the restaurant job back.

In Los Angeles County, investigators said that, like the Half Moon Bay suspect, the gunman in Monterey Park had legally purchased the semiautomatic weapon with which the massacre was committed. According to two law enforcement officials briefed on the matter who requested anonymity because of the sensitivity of the investigation, Mr. Tran had bought his MAC-10, which was equipped with an extended capacity magazine, in the 1990s, before California began imposing a series of bans on such rapid-fire weapons.

Officials said they are still trying to determine if the gun had been altered in a way that would have made it illegal to possess at the time of the shooting. Detectives also have seized two other guns in the investigation: the handgun the police say Mr. Tran used to shoot himself as pursuing officers closed in on him Sunday after a regionwide manhunt and a rifle found at his home in a Hemet, Calif., trailer park.

In Southern California, the authorities released the names of the 11 people who were killed in the Saturday night shooting as families mourned the loss of beloved parents, grandparents, aunts, uncles, brothers and sisters.

The Los Angeles County coroner’s office, which has spelled the names of victims differently at various points this week, on Tuesday identified the six women as Diana Man Ling Tom, 70; Muoi Dai Ung, 67; My My Nhan, 65; Lilian Li, 63; Hongying Jian, 62; and Xiujuan Yu, 57. The five men were identified as Chia Ling Yau, 76; Ming Wei Ma, 72; Yu Lun Kao, 72; Valentino Marcos Alvero, 68; and Wen Tau Yu, 64.

New details emerged on Tuesday that were both heartbreaking and horrific.

Shortly after 10 p.m. on Saturday, Ms. Nhan, 65, and her dance partner that night, an older man, decided to leave the Lunar New Year celebration at Star Ballroom Dance Studio a little early.