The conflict over Nagorno-Karabakh, which lies within Azerbaijan, some 270 kilometers (170 miles) west of the capital Baku, first erupted in 1988 when it declared its independence from Azerbaijan and moved to join Armenia.
Over 30,000 people were killed on both sides in fighting between 1988 and 1994, and over 100 died following a 1994 ceasefire.
Ilgar Verdiyev said a 24-year-old warrant officer was killed January 17 in the Fizuli District in what he claims was a violation of a ceasefire agreement by the Armenian side.
Nagorno-Karabakh remains under Armenian military control, and tensions between Azerbaijan and Armenia have persisted as a result.
The Defense Ministry of the self-proclaimed republic in turn refuted the allegations of the attack.
"There was no gunfire on that day, as far as I know, and generally speaking, the Karabakh side is committed to the ceasefire agreement," said Senor Asratyan, the ministry's press secretary.
Azerbaijan's Foreign Minister Elmar Mamedyarov and his Armenian counterpart, Vardan Oskaryan, are expected to meet in Moscow January 23 in another attempt to reach a compromise on the region's status.
Residents of Nagorno-Karabakh overwhelmingly voted in a referendum on the republic's Constitution last month to reaffirm the predominantly Armenian region's independence from Azerbaijan.
More than 100 international observers and journalists from Russia, France, the United States, Italy, Israel, Serbia and other countries monitored the referendum.
The Azeri leadership, which is determined to restore its control over the separatist region, dismissed the referendum as a farce.
The United States, the European Union and other international organizations, including the Organization for Security and Cooperation in Europe (OSCE), said no country will recognize the referendum's results.
