Mali's government on Monday declared a ten-day state of emergency from midnight after what security sources say follows a series of threats from unnamed jihadist groups.
An Islamist insurgency simmering in the West African country since French forces drove the militants out of key northern towns two years ago has intensified in recent months.
Unknown jihadists attacked a luxury hotel in November, killing 20 people including many foreigners, in the latest strike on the country's once stable southern capital Bamako.
Mali's government then declared a state of emergency but it has since expired.
"The state of emergency aims to give the relevant authorities the means to allow them to better identify and counter any project threatening people's safety...," according to the government statement, without giving details.
Two security sources said threats issued by jihadist groups had prompted the announcement. One of them said this followed a meeting of Islamist militant leaders in the northern Kidal region last week.
Many armed fighters operate in Mali's vast northern desert, including some with links to al Qaeda, and other secular groups drawn from the Tuareg community seeking independence for a region they call Azawad.