Petty Officer First Class Timothy Jackson was a member of a group of Navy SEALs who decided to launch a raid on a drug dealer's house following the death of David Ramirez, another SEAL who was a member of the group.
The SEALs invaded the scene, only to discover Douglas Grozen and his partner, Mekowitz already there. However, Grozen, a corrupt cop killed Mekowitz before firing on the SEALs who were already heading back into the ocean.
Unfortunately, Jackson was caught in the crossfire, being shot in the left or right side of his body and he eventually succumbed to his injuries, dying of the gunshot with his body later wawshing up on a beach somewhere outside Los Angeles. The local authorities eventually alerted NCIS to the discovery with Agents G. Callen and Sam Hanna being dispatched arrived to investigate where they confirmed that the body was that of Timothy Jackson.