By Kristen Johanson

PHILADELPHIA (CBS) — Mourners, including hundreds of police officers, gathered Saturday morning, paying their last respects to fallen Philadelphia Police Officer Robert Wilson III.

Officers began forming in a Caisson Procession at 5am. Bagpipes and drums accompanied Philadelphia officers as they marched from the 3000 block of JFK Boulevard to the Palestra at the University of Pennsylvania, where the viewing started at 7am.

Two white horses led the carriage holding the black casket through University City, while rain steadily fell on the Caisson Procession.

Mayor Michael Nutter and Police Commissioner Charles Ramsey shared a silent moment side by side in the rain while officers filed into the Palestra for the viewing.

Commissioner Ramsey and Mayor Nutter stand side by side in a silent moment. (credit: Kristen Johanson)

Commissioner Ramsey and Mayor Nutter stand side by side in a silent moment. (credit: Kristen Johanson)

During the viewing, a long line of officers and mourners formed, waiting to pay their respects. The viewing will be followed by a service at 10:30am.

The internment will take place later today at Fernwood Cemetery in Lansdowne.

Hundreds of police from Philadelphia and across the country also attended a viewing  for Officer Wilson on Friday night.

Officer Wilson was shot and killed during a shootout with two suspects attempting to rob a video game store in North Philadelphia on March 5.

The suspects, identified as brothers Ramone Williams and Carlton Hipps, have been charged with first-degree murder.