A man walks past a damaged building in a residential area in Ganja, Azerbaijan's second largest city, near the border with Armenia, after rocket fire overnight by Armenian forces, Oct 11, 2020. (PHOTO / AP)

Armenia and Azerbaijan have accused each other of breaking a cease-fire within hours of the agreement taking effect in the Nagorno-Karabakh region on Saturday.

The Azerbaijani prosecutor general's office said five people were killed and 28 injured on Sunday during a missile attack on Ganja, Azerbaijan's second-largest city.

According to prosecutors, the missile struck an apartment building in the city center. The country's emergencies ministry said the building was destroyed. Earlier, rescuers said 17 survivors had been pulled from the rubble.

Armenia's defense ministry denied any truce violations by Armenian forces and said the pact was "largely holding" despite Azerbaijani "provocations", to which the Armenian troops responded in kind, it said.

The Azerbaijani prosecutor general's office said five people were killed and 28 injured on Sunday during a missile attack on Ganja, Azerbaijan's second-largest city

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The truce between the Caucasus neighbors was announced as taking effect from noon on Saturday.

The Azerbaijani prosecutors reported another missile attack in the country on Sunday morning.

"At about 4:00 local time, the Armenian armed forces carried out a missile attack on the major Azerbaijani industrial city of Mingechevir, which is 100 kilometers from the zone of the hostilities, and the Mingachevir Hydroelectric Power Plant located there," the prosecutors said.

Azerbaijan's Foreign Minister Jeyhun Bayramov said "conditions for implementing the humanitarian cease-fire are currently missing "amid the continuing Armenian shelling.

Artsrun Hovhannisyan, a representative of the Armenian defense ministry, acknowledged that fighting had continued.

"Throughout the night and until the hour of the cease-fire, fighting had been ongoing," Hovhannisyan said on Saturday. "Since 12:00 the cease-fire has been largely observed, but the adversary occasionally resorted to provocations."

Hovhannisyan said Azerbaijan's shelling of an area near the town of Kapan in southeastern Armenia killed one civilian.

The accusations from both sides raised questions about how meaningful the truce, brokered by Russia, will turn out to be.

The deal, clinched after marathon talks in Moscow advocated by Russian President Vladimir Putin, was agreed in a joint statement by the foreign ministers of the three countries－Zohrab Mnatsakanyan of Armenia, Jeyhun Bayramov of Azerbaijani, and Sergei Lavrov of Russia－early on Saturday.

Under the deal, Armenia and Azerbaijan are to exchange prisoners, other detainees and the bodies of victims of the conflict under the mediation of the International Committee of the Red Cross.

'Substantive negotiations'

The countries agreed to begin "substantive negotiations" for a peaceful settlement as soon as possible, with the co-chairs of the Organization for Security and Cooperation in Europe Minsk Group acting as mediators.

The parties have also confirmed "the invariability of the negotiations format", but Hovhannisyan and Bayramov said the truce would last only for as long as it took the Red Cross to arrange for the exchange of bodies.

The Red Cross said it stood ready to facilitate the handover of bodies of those killed in action and the simultaneous release of detainees.

The deal was reached in accordance with what Putin, Azerbaijani President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan have agreed upon, the Russian foreign ministry said.

Moscow has repeatedly called for a cease-fire and a political settlement of the differences. The closed-door meeting of the three foreign ministers lasted about 10 hours, marking the longest one devoted to Nagorno-Karabakh over the past two decades.

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On Saturday, the Secretary-General of the United Nations Antonio Guterres welcomed the agreement.

He had called for the truce to be respected and for a swift agreement on the specific parameters of the cease-fire.

Guterres appealed to the international community to support the agreement and to continue to encourage the parties to resolve their differences through peaceful means.

Turkey welcomed the deal but said much more was needed.

"The humanitarian cease-fire is a significant first step but will not stand for a lasting solution," the Turkish foreign ministry said in a statement. "Turkey will continue to stand by Azerbaijan in the field and at the table."