Azerbaijan launched "local anti-terrorist activities" in Karabakh to restore constitutional order by disarming and forcing the withdrawal of Armenian military formations after six Azerbaijani citizens were killed in separate mine blasts in the breakaway region.
Baku blamed Armenian separatists for the death of the four Azerbaijani police officers and two civilians.
"Anti-terrorist operations in the region of a local character have begun," Baku's defence ministry said, adding it was using "high-precision weapons on the front line and in depth" as part of the operations.
The ex-Soviet neighbours have been locked in a decades-long dispute over the mountainous region, going to war twice in the 1990s and in 2020.
It said it was only targeting legitimate military targets using what it called high-precision weapons and not civilians or civilian infrastructure as part of what it called a drive to "restore the constitutional order of the Republic of Azerbaijan".
It said it had informed a Russian peacekeeping force in the area along with a Turkish-Russian monitoring centre which is meant to help ensure a 2020 ceasefire is upheld.
Earlier in the day, Baku said four interior ministry staff had been killed when their truck was blown up by a mine near a tunnel construction site on Tuesday. Another mine had killed two civilians, also in a truck, it said.
The blast happened "in the zone of temporary deployment of the Russian peacekeeping contingent," deployed by Moscow in 2020 as part of a ceasefire deal between Armenia and Azerbaijan.
There was no immediate response from the ethnic Armenians authorities in Karabakh.
Armenia said on Monday that accusations that its own armed forces had placed mines on Azerbaijani territory were false.
The landmine incidents occurred a day after badly needed food and medicine was delivered to Karabakh along two roads simultaneously, a step that looked like it could help ease mounting tension between Azerbaijan and Armenia.
Ties remain severely strained however.
Azerbaijan's defence ministry on Tuesday accused "illegal Armenian armed groups" of jamming the GPS navigation of a passenger jet flying from Tbilisi in Georgia to Baku.
Asking to withdraw its armed forces
Baku on Monday demanded Armenia to immediately withdraw its armed forces from the Azerbaijani territory of Karabakh, and abolish the military and administrative structure of the so-called regime in the region.
There are more than 10,000 Armenian armed forces loyal to the so-called regime in Karabakh, it said, adding that the forces have over 100 tanks and other armored vehicles, more than 200 heavy artillery weapons, including volley rocket systems, and more than 200 mortar systems.
It added that Armenian forces have violated the tripartite declaration signed on Nov. 10, 2020, and Yerevan is preparing for a new attack.
Karabakh, internationally recognised as part of Azerbaijan, broke from Baku's control in the early 1990s after a war. Azerbaijan recaptured swathes of land in and around it in a 2020 war.
