LOS ANGELES (AP) — A Los Angeles police officer serving in Afghanistan has been killed by a roadside bomb.

Marine Staff Sgt. Joshua J. Cullins died Monday.

The 28-year-old reservist was an explosive ordinance disposal officer. The Los Angeles Times says he died from injuries caused by a bomb that detonated as his unit investigated an earlier explosion in Helmand province.

The Times say Cullins recently recovered from a concussion he suffered in July while dismantling another bomb. In August, fellow LAPD officers sent him a videotaped get-well card urging him to come home safely.

Cullins is the second LAPD officer killed in Afghanistan. A bomb killed SWAT officer Robert J. Cottle along with another Marine in March .

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