London (CNN Business) Forty-nine journalists were killed this year, 57 are being held hostage and 389 are currently in prison, nonprofit group Reporters Without Borders said Tuesday.

In its annual review, the Paris-based group found that the number of journalists killed in 2019 was the lowest since 2003, representing a "historically low" figure compared with an average of 80 journalists killed per year over the past two decades.

The fall in the number of journalists killed is due to a reduction in the number of journalists killed in war zones, Reporters Without Borders said, noting that 941 journalists have been killed over the past 10 years.

While conflicts in Syria, Iraq, Yemen and Afghanistan were less deadly for journalists than in previous years, the number of deaths in countries not at war remained "much the same" as in previous years, the group noted.

Some 63% of journalists killed worldwide were murdered or deliberately targeted, Reporters Without Borders added.