NYPD members saluted the coffin of slain cop Wenjian Liu Saturday, as other mourners bowed and lit incense in a somber wake that fused the department's tradition with Buddhist ritual.

The wake will be followed by a funeral at 11 a.m. Sunday, the second of two farewells for the officers shot and killed by a cop-hating assassin while sitting in a patrol car in Brooklyn on Dec. 20. The double-murder has led to a crisis in Mayor Bill de Blasio's relationship with rank-and-file police.

Police from as far as Los Angeles and New Orleans were among those who lined up around the block for Liu's wake, which also drew mourners from the city's Asian-American communities.

Cops and civilians held umbrellas against snow and rain outside the funeral home in the Dyker Heights neighborhood of Brooklyn, two miles from the home where Liu, 32, had recently moved with Pei Xia Chen, the woman he married two months before his death.

Liu's widow and parents sat clenched in "intense suffering" in the funeral home, where the officer's body lay in an open casket, Rep. Peter King said.

"His wife, the widow, looks absolutely devastated," said King (R-Seaford), as he left the wake. "Very somber, quiet sorrow." Speaking of Liu's parents and widow, he said, "Their bodies were hunched very tightly. Very controlled sadness."

Officers filed past the coffin and photos of Liu as some mourners bowed three times -- a Buddhist custom, said Winnie Greco, a liaison to the Chinese-American community for Brooklyn Borough President Eric Adams.

There were no signs of the recriminations that have roiled the city since Ismaaiyl Brinsley, 28, gunned down Liu and Det. Rafael Ramos outside a Bedford-Stuyvesant housing project. Brinsley, who fatally shot himself before he could be apprehended, had posted online about his desire to kill police.

Liu and Ramos were posthumously promoted to detective first grade.

De Blasio paid respects inside the funeral home for about 15 minutes Saturday. Mourners also included Gov. Andrew M. Cuomo, Police Commissioner William Bratton, former deputy mayor Joseph Lhota and Steven McDonald, an NYPD officer from Malverne left quadriplegic by an on-the-job shooting in 1986.

FBI Director James Comey was scheduled to attend the funeral Sunday.

Bratton had asked officers in a memo to refrain from turning their backs at the wake, saying memorials are "about grieving, not grievances."

Los Angeles Police Department Officer Hannu Tarjamo said he and about 20 LAPD officers flew in Friday night to support the NYPD.

"When it happens here, it happens to us," he said. "It's an act of savagery that should be condemned by society."

Liu, who moved to the United States with his parents when he was a teenager, is the first Chinese-American NYPD officer slain in the line of duty.

Peter Koo, a city councilman who represents the Flushing, Queens, area, said Liu's mother clenched his hand and cried during the wake. "It was sad, and a somber atmosphere," he said.

Ruby Chan, of College Point, Queens, said she waited in line for two hours to hand an envelope of money to the family, a common gesture at memorials in Chinese culture.

"I'm from Hong Kong and I feel very badly for them," she said. "It's not much, but he was their only son and I was worried about his parents."

Signs posted on homes and businesses in the neighborhood expressed support for the NYPD. Several read: "Hero Det. Liu."

The mourners were a mosaic, crossing ethnic and religious lines.

At St. Rosalia-Regina Pacis Parish up the street, a dozen Italian women sang in their native language to Saint Padre Pio, asking for his aid.

"God says to love one another and what happened to Det. Liu is unspeakable," said Rosa Loconsole.

Guan Zi Yuan, 76, of Chinatown, hung a pair of banners with Chinese calligraphy and English writing on a boarded-up former bagel shop across from the funeral home.

In English, it read: "To Mr. Wen Jian Joe Liu, to be remembered forever by posterity. Immortal."

With Maria Alvarez