Marta Martel, 81, played bingo with Patricia Serrano at Los Sures Senior Center on South 4th Street for the past six years, she said. View Full Caption DNAinfo/Gwynne Hogan

WILLIAMSBURG — Friends and relatives mourned a beloved grandmother and salty-mouthed bingo player Monday at a memorial service and the senior center nearby where she'd played almost every weekday for the last eight years.

Patricia Serrano, 68, who died after collapsing on the fire escape trying to escape a blaze in her building at 232 Metropolitan Ave. on March 28 was a pillar of Williamsburg's south side community, friends said, a neighborhood volunteer and dedicated church member, known for her ferocious sailor's mouth and as a lover of gambling and, most of all, bingo.

"She was obsessed with bingo," her grandson Eric Nieves Jr. with a smile, following Monday's memorial First Spanish Presbyterian Church at 157 S. Third St., where Serrano was a member. Her love for the game was so intense that family decided to bring it into her burial ceremony at Mount Olive Cemetery, they said.

"When we let go of the balloons we screamed 'bingo'," said Serrano's daughter Carolyn Nieves, 39.

Among the mourners gathered Monday, many knew Serrano through Los Sures David Santiago Senior Center on South 4th Street where she'd worked as a volunteer and would also go to dance, play bingo and socialize most days since she turned sixty.

"When she didn't win, [she'd say] 'F--k! I'm missing this number!'" said Merecedes Melendez, 68, in Spanish, who'd been friends with Serrano since high school, recalling Serrano's fiery antics.

Melendez said she'd most miss, "the fighter in her."

Serrano's spunk endeared her to many whose paths she crossed, including Sonia Iglesias, the director at the senior center.

"She was feisty," Iglesias said. "When she had something to say she'd say it," also highlighting her spicy vocabulary that emerged in the heat of a bingo game.

"[Bingo is] what she did, [it's] what she loved."

The day the seniors at the center got wind of Serrano's sudden death, they'd considered postponing the bingo game, Iglesias said, but they soon ruled that out, at the behest of some seniors as well as Serrano's family.

"We should play bingo, because that's what she loved," said Felix Pacheco, 71, who sat at Serrano's regular table in the far back corner of the room.

Serrano who was born in Puerto Rico, had a 35-year-long career as a nurse first at a school and later at Woodhull Hospital, according to an obituary at her service. Since her retirement she'd remained an active community member, volunteering at the Los Sure's David Santiago Senior Center, helping out at a food pantry for more frail senior citizens, friends and family members said.

A dedicated community member until the end, neighbors said that before trying to save herself the day of the fire that lead to her death, Serrano had run around her floor knocking on doors warning them of the blaze, DNAinfo earlier reported.

"I'm not going to leave unless my neighbors [are OK]," her grandson Eric Nieves Jr., recalled Serrano saying during the chaotic evacuation of their building on Metropolitan Avenue moments before her death.

"I heard her yelling, she was knocking on doors," said Marisol Sandoval who lived on the third floor of the building with Serrano. "I got out in time, [because of] her...I knew how to react and get out."

During their escape, Serrano began having a seizure on the fire escape, and firefighters eventually brought her out on a stretcher. She soon went into cardiac arrest and was later pronounced dead at Woodhull Hospital, according to fire officials and her grandson Eric.

As of Monday, the medical examiner's office had not yet determined Serrano's cause of death, spokeswoman Julie Bolcer said.

Investigators believe that the fire started because of a faulty outlet, sources said. FDNY had visited the day before and the day of the fire because of an outlet that was sparking and had warned the super to fix the problem, DNAinfo earlier reported.

They'd shut off power to that outlet and the super called an electrician who didn't show, according to Thomas Servello, a spokesman for Los Sures Management Company, affiliated with the non profit Southside United HDFC where Serrano also volunteered.

Servello said that the electricity was still shut off to that outlet and the time of the fire and they were not sure how it had begun.

"Were' still looking at it," Servello said.

Servello also disputed the FDNY's claim that there were no functional smoke detectors at the scene of the fire.

#FDNY Fire Marshals: Cause of 3/28 2nd alarm, 232 Metropolitan Ave #Brooklyn was accidental, electrical. No working smoke alarm present — FDNY (@FDNY) March 29, 2016

"That's not what we have in file," he said.

"Patricia was loved by everyone and she did a lot of really hard work for our nonprofit," Servello said. "This is someone that we miss a lot."

Eric Nieves Sr., Serrano's son who lives in Florida, said he was disappointed at how Los Sures Management was handling the situation and said the family is still looking for answers about what started the fire.

"She volunteered for them, she paid her rent to them," Nieves said. "They're not being forward."