UPDATED 05/03/11 2:03 p.m.

CHICAGO (CBS) — The Fraternal Order of Police on Tuesday held a memorial to honor four Chicago Police officers who have died in the line of duty within the last year.

The service was held at the Fraternal Order of Police Lodge No. 7, 1412 W. Washington Blvd. It honored officers Thomas Wortham, Thor Soderberg, Michael Bailey and Michael Flisk.

Wortham was shot and killed in a robbery near his parents home on May 20 of last year, in the 8400 block of South King Drive.

Soderberg was shot and killed as he walked to his car at the end of a shift at the police facility at 61st Street and Racine Avenue on July 7.

Bailey was shot and killed while cleaning out his car at his home near 74th Street and Evans Avenue on July 18.

Flisk was shot and killed as he investigated a burglary in a garage behind the 8100 block of South Burnham Avenue on Nov. 26. Also killed in the shooting was retired Chicago Housing Authority police officer Stephen Peters.

Suspects have been charged in all the cases except that of Bailey, which remains unsolved.

Family members of the officers will be honored guests, and several speakers will address the losses to the department over the past year.

The service was held at noon Tuesday.