Thousands of officers in dress uniform gathered in formation yesterday along a12-block expanse of Flatbush Avenue outside the mortuary where Officer Russel Timoshenko was eulogized.

Timoshenko, the young officer gunned down in Brooklyn last week, was buried with full honors at New York City Police Department funeral.

The Eastern Orthodox funeral service for Timoshenko, an immigrant from Belarus, was conducted in both English and Russian and was about two hours long, during which a priest exchanged songs of prayer with a small choir. In Bishop Gabriel Chemodakov’s eulogy, he spoke directly to the parents of the slain officer, Leonid and Tatiana Timoshenko, in their native language before translating his remarks into English.

One of Timoshenko’s best friends, David Levin, who was born at the same hospital in Belarus, described the slain officer as a scholar whose American dream was to join the NYPD.

“It was his senior year in college when this talented honor student chose this new direction for his life,” he said. “It provided him with a means to have a direct positive impact on the community.”

A throng of male and female police officers sitting at the back of the chapel wore gold pins bearing the number 71 — Timoshenko’s precinct — and quietly sobbed throughout the funeral.

“Russel never talked about the dangers of the job,” the police commissioner, Raymond Kelly, said in his eulogy. “He was simply devoted to work and the opportunity it gave him to safeguard the city.”

Mayor Bloomberg also spoke at the service, and told mourners that Timoshenko had been posthumously promoted to detective.