VIDEO: Thousands Attend Funeral for Slain NYPD Sergeant

An estimated 12,000 people mourned NYPD Sgt. Paul Tuozzolo on Thursday, hailing him as a generous man who made the ultimate sacrifice, reports the New York Daily News .

Tuozzolo, 41, a father of two young boys, was shot in the Bronx last week as officers approached an ex-con cowering in a crashed Jeep Cherokee. The gunman shot and killed Tuozzolo, but not before Tuozzolo could warn Sgt. Emmanuel Kwo.

"Sgt. Paul saved my life, Ed," Ed Mullins, president of the Sergeants Benevolent Association, recalled Kwo telling him. "He saved my life. He saw something we didn't see. He yelled at us, 'Gun! Gun! Gun!'"

Kwo, 30, was grazed in the leg before Elwin Martinez, a Police Academy recruit, killed the shooter. Kwo and Martinez attended the funeral Mass in Massapequa, L.I., on Thursday.

Mayor de Blasio told Tuozzolo's two sons, ages 4 and 3, that they have their father's strength. One of them clutched a toy car.

"His final act on this Earth, he served in exemplary fashion," de Blasio said at St. Rose of Lima Church, bowing his head in front of Tuozzolo's casket before making his remarks. "He could have sent his fellow officers, but he took the lead and he gave his life protecting his fellow officers and all of us."

With 19 years on the job and only months from being eligible for retirement, Tuozzolo chose the day-tour patrol, putting him back on the streets.

Outside the church, six pallbearers carried Tuozzolo's burgundy casket as his wife, Lisa, sobbed and comforted their sons. Nine helicopters flew in formation overhead. More than 10,000 law enforcement officers lined the streets. All of Massapequa seemed to be in mourning.

O'Neill posthumously promoted Tuozzolo to sergeant special assignment, giving his family additional financial benefits.