Well, besides all the criminals, here are the main ones:
Special Agent Kate Todd - Kate was shot by Ari Haswari (Ziva's half brother) at the end of season 2
Ari Haswari - Ari was Ziva's half brother, but she shot him to protect Gibbs. It was either the end of the second season or the beginning of the third, I can't remember exactly
Director Jenny Shepard - Jenny died at the end of season 5. She was also shot. She would have died anyway because she had a terminal illness, but no one knows exactly what was wrong with her, except Ducky, and I think possibly Abby
Michael Rivkin - Michael Rivkin was a rogue Mossad officer who was also Ziva's boyfriend. Tony shot him at the end of the sixth season after they got in a fight
They are the main ones but some other not so major characters are:
Agent Lee- who was in Legal until moved to Gibbs's team in Season 6. She was a suspected mole but was blackmailed by someone kidnapping her sister. She let Gibbs shoot her so that he could also kill the man responsible for everything.
Agent Langer- Was one of the agents brought in season 6. Agent Lee killed him and as a result he was suspected to be the mole.
Agent Paula Cassidy- Had previously worked with Tony and Gibbs and when her team was killed in by a suicide bomber she teamed up once again with team Gibbs to catch the person who did it when the details start to look shady. She was killed when they found the real suicide bomber who was going to blow up a gathering of all the notable peace keeping people from around the Middle East.
La Grenouille (The Frog)- Killed by Jenny Shepard for revenge as he killed her father.
As for Kate, she should have lived, the bullet went right through her head. Since the brain is in two hemispheres, it should have gone right through. All she would have needed would be stitches.
A funny Marine gets killed in the ncis episode Code of Conduct.
Liza Lapira, who played Agent Lee, was killed during season 6 of NCIS. She was a traitor. Gibbs shot her
Washington DC
Ziva killed her half-brother Arie.
he was killed by the port to port killer
Tony was almost killed by bubonic plague from a biological attack on NCIS.
Official (Vance/NCIS) coverup: She gets blown up in a gas explosion and fire in her townhouse. Plot: She gets killed in a four-against-one shoot-out at the Decker diner, in retaliation for her and Gibbs' attempted assassination of KGB agent/russian mobster Natashia, decades earlier.
Liza Lapira, who played Agent Lee, was killed during season 6 of NCIS. She was a traitor. Gibbs shot her
An assassin from North Korea will be the next one to be killed on ncis show.
Rocky Carroll plays the character of the NCIS Director Leon Vance. Leon Vance joined the NCIS Cast in Season 5. His first appearance was on Episode 14 of NCIS Season 5 "Internal Affairs". He has been with the team ever since. He also took over as the NCIS Director when the existing character Jenny Shepard gets killed at the end of season 5
Washington DC
Ziva killed her half-brother Arie.
he was killed by the port to port killer
Tony was almost killed by bubonic plague from a biological attack on NCIS.
Season 5, Episode 18, Judgement day Part 1, her death is investigated in part 2
It had to have been right after season 6 of NCIS then if you watch NCIS season 7 then macy gets murdered in Annapolis
No, Dr. Donald "Ducky" Mallard did not get killed off in the final episode of NCIS. He retired from his role as the Chief Medical Examiner but remained alive.
The episode is 'Judgment Day'