Busloads of police officers are converging on a church for the funeral of a young New York City police officer who was killed on patrol.

Snipers are watching from a nearby elementary school roof and authorities have imposed a 3-mile no-fly zone above the Long Island church where Officer Brian Moore's funeral Mass is scheduled for Friday.

The 25-year-old died Monday, two days after he was shot in Queens. He and his partner had stopped a man suspected of carrying a handgun. The man opened fire.

As many as 30,000 officers from across the country are expected at the funeral in Seaford. Among the mourners are relatives of Officer Wenjian Liu (WEHN'-jihn LOO'), one of two New York City officers killed in an ambush in December.

Copyright 2015 The Associated Press.