An estimated 20,000 police officers withstood the bitter cold weather to attend yesterday morning’s South Bronx burial mass for the second New York police officer killed in as many weeks.

“It’s almost too hard to believe and almost too hard to bear,” Mayor Bloomberg said to the mourners in St. John’s Chrysostom Church, at 985 East 167th Street.

It was just eight days ago that a comparable number of officers came from all over the world to attend the funeral of Dylan Stewart, the first police officer gunned down this year.

At yesterday’s memorial service for Daniel Enchautegui, 28, who was shot and killed while investigating a burglary at an apartment building next door to his Bronx home, more than 1,500 people crowded into the church while the rest hovered outside in weather well below the freezing mark.

Mr. Bloomberg called Enchautegui’s death as well as the shooting deaths of Stewart, 35, who died during a car chase on November 28, and detectives Robert Parker, 43, and Patrick Rafferty, 39, who were shot in September 2004 while trying to arrest a man on charges of domestic violence, “senseless tragedies.”

An actor, Lillo Brancato Jr., 29, and his friend Steven Armento, 48, have been arrested for allegedly murdering Enchautegui.

Despite having been shot, Enchautegui demonstrated “astonishing accuracy,” when he successfully fired seven shots at the suspects, Mr. Bloomberg said. Police initially said that the officer fired eight shots.

The mayor, the city’s police commissioner, Raymond Kelly, and Enchautegui’s sister, Yolanda Rosa, 41, painted a picture of Enchautegui as a committed officer and family man who could maintain a sense of humor through the worst of times.

Enchautegui had a close relationship with his parents, visiting them almost daily, Mr. Bloomberg said. A rock and roll fan, Enchautegui would turn the radio dial in his squad car to 92.3 FM K-Rock at the start of his day. Enchautegui had a passion for history and enjoyed crime novels, camping, and hunting.

His favorite television program was the animated show, “The Simpsons,” Mr. Bloomberg said, and Enchautegui was nicknamed Homer after the character of the same name from the show.

Growing up in the Bronx, Enchautegui always knew he wanted to be a police officer, the mayor said.

He was known in his South Bronx precinct as “smart and thoughtful,” Mr. Kelly noted during his remarks. The commissioner credited the slain officer with arresting 28 people, one-third of whom were alleged felons, in his three years on the force.

Mr. Bloomberg posthumously promoted Enchautegui to detective first-grade, which prompted a standing ovation from the sea of blue packed into the pews.

Enchautegui was a top student at the Police Academy and graduated from John Jay College of Criminal Justice in 2001 with a B.S. in police studies. While in school, he worked as a security guard at John Jay, a school spokeswoman, Doreen Vinas, said.

The chairwoman of the Department of Law, Police Science, and Criminal Justice Administration, Maria Haberfeld, taught Enchautegui for three consecutive semesters and recalled him with fondness.

“From time to time you have a student you remember quite well … and he was one of them,” Ms. Haberfeld said. “We found a common language; he was very much into police and law enforcement.”

This year’s two police fatalities have elicited renewed efforts to strengthen gun laws. When the crowd fell quiet following Mr. Bloomberg’s remarks, a man wearing a button for “New Yorkers Against Gun Violence” hollered, “Get rid of illegal guns.”

The president of the Patrolmen’s Benevolent Association, Patrick Lynch, later made an appeal to “stop the illegal guns” on the streets.

As at Stewart’s funeral, yesterday’s service ended with officers carrying the coffin draped in the traditional police flag on their shoulders to the awaiting hearse. Police Department helicopters flew overhead in the missing-man formation. The procession ended with the sound of the bagpipes, as Enchautegui’s family and friends made their way to St. Raymond’s Cemetery in the Bronx.