The report came a day after the media freedom group Reporters Without Borders issued its own tally, saying the USA was among the top five deadliest countries for journalists this year for the first time, with six dead.
"The hatred of journalists that is voiced, and sometimes very openly proclaimed, by unscrupulous politicians, religious leaders and businessmen has tragic consequences on the ground", he said in a statement.
Four of the American journalists were killed in the Capital Gazette shooting in Annapolis, Maryland, on June 28.
The number of journalists killed on duty rose in 2018 and the number murdered in reprisal for their work doubled, the Committee to Protect Journalists (CPJ) reported on Wednesday.
On the other hand, the number of journalists killed in combat or crossfire dropped to the lowest since 2011.
The recent uptick in killings comes as the jailing of journalists hits a sustained high-adding up to ongoing global crisis of press freedom.
After a two year decline, the number of journalists killed for their job was once again on the rise in 2018.
RSF Secretary-General Christophe Deloire said the violence against journalists "has reached unprecedented levels", calling the situation "critical".
A total of 80 journalists were killed, including non-professional journalists and media workers. Sixty-three professional journalists were killed, and 49 of those deaths were targeted murders, according to the report.
The kingdom has said Khashoggi was killed inside its Istanbul consulate on October 2 in a "rogue operation" led by the then deputy intelligence chief Ahmad al-Assiri and royal court advisor Saud al-Qahtani, both of whom have been sacked.
"The Kingdom of Saudi Arabia rejects the position expressed recently by the US Senate, which was based upon unsubstantiated claims and allegations, and contained blatant interferences in the Kingdom's internal affairs, undermining the Kingdom's regional and worldwide role", its Foreign Ministry said in a. WWE came under fire in the weeks and days leading up to Crown Jewel due to the controversy surrounding the death of journalist Jamal Khashoggi and Saudi Arabian Crown Prince Mohammed bin Salman's possible role in the murder.
"Our community has rallied around us to show they understand who we are, and that we are not the enemy of the people", it continued. More than half of the journalists killed were deliberately targeted, the other 31 were caught in violence. Thirteen journalists were murdered for their work in the country in 2018, according to CPJ's report, and 48 journalists have been killed in Afghanistan since 1992.
Khashoggi, the reporters at the Capital Gazette, and the imprisoned Reuters' journalists Wa Lone and Kyaw Soe Oo were featured last week in Time Magazine's Person of the Year issue, honoring "The Guardians and the War on Truth".
Fake news is the likening the conditions for journalists in Afghanistan to America.
China continued to be the world's biggest jailer of journalists, with 60 now detained in the country according to the report.