Armenian opposition supporters and relatives of servicemen wounded in border clashes between Armenia and Azerbaijan gather in front of the parliament to call for the Armenian prime minister's resignation, in Yerevan on September 13, 2022.

Despite earlier claims of a ceasefire, fighting between Azerbaijan and Armenia continued Wednesday, a day after nearly 100 soldiers died in clashes, according to the Azerbaijani and Armenian ministries of defense.

Russia suggested it had brokered a ceasefire between Armenia and Azerbaijan in a statement Tuesday, but it proved short-lived.

The Russian-mediated ceasefire was “almost immediately broken,” according to US National Security Council coordinator for strategic communications John Kirby.

Armenia’s Ministry of Defense on Wednesday accused Azerbaijan of attacking again, claiming artillery, mortar and “large-caliber firearms” had been fired at three Armenian towns, including Jermuk near the border between the two countries.

In a series of tweets, the ministry insisted that “the entire responsibility” for the current clashes and any future developments falls on Azerbaijan. Armenia’s government said Tuesday that at least 49 Armenian service members had been killed in action.

Azerbaijan, meanwhile, tweeted Wednesday that some of its military units were also being subjected to artillery fire. In a statement, its Ministry of Defense said a criminal case had been opened into the case of two civilians injured as a result of the ongoing conflict with Armenia.

“Two civilians were wounded as a result of a large-scale provocation committed on the night of September 12 by the Armenian armed forces,” the statement read. “The facts are currently being investigated.”

Fifty Azerbaijani servicemen were killed in deadly clashes on Tuesday, the Azerbaijani Ministry of Defense said in a statement. They included 42 members of the Azerbaijan Army and eight members of the State Border Service, it said.

An ambulance moves on a street near a military hospital in Yerevan, Armenia, following night border clashes on September 13, 2022.

If the fighting between Armenia and Azerbaijan continues, it could place key oil and gas pipelines in jeopardy, exacerbating issues with energy supplies already disrupted by the war in Ukraine, according to Reuters.

For decades, Armenia and Azerbaijan have been engaged in a dispute over the Nagorno-Karabakh region, a landlocked area between Eastern Europe and Western Asia that is populated and was controlled by ethnic Armenians but located in Azerbaijani territory.

The unrest in the region dates back to the collapse of the Soviet Union, when the region, backed by Armenia, declared independence from Azerbaijan. Azerbaijan has long claimed it will retake the territory, which is internationally recognized as Azerbaijani.

In November 2020, renewed fighting broke out in the region for almost two months, killing at least 6,500 people, according to Reuters. Hostilities ended after Armenian-backed separatists agreed to relinquish control over territories in the restive region. Russia helped broker the ceasefire deal between the two countries, which saw President Vladimir Putin send peacekeeping forces along the contact line in Nagorno-Karabakh.

“As far as we know, that peacekeeping presence is still there,” Kirby told reporters Tuesday. When asked if Russia could reposition its troops to Armenia, Kirby said: “We haven’t seen any indication that Russian forces are repositioning now.”

On Tuesday, Armenia called on Russia to implement a 1997 defense treaty that stipulates the countries will defend each other’s territorial integrity and sovereignty in the event of an attack by a foreign country.

“A decision was made to officially apply to the Russian Federation for the implementation of the provisions of the Treaty of Friendship, Cooperation and Mutual Assistance, to the Collective Security Treaty Organization and the UN Security Council regarding the aggression against the sovereign territory of the Republic of Armenia,” a statement from the Armenian Prime Minister’s office read.

The request followed a session with the Armenian Security Council and a call between Armenian Prime Minister Nikol Pashinyan and Putin, according to a statement from Pashinyan’s office.

Just hours after Moscow said it had facilitated a ceasefire between the two nations, US Secretary of State Antony Blinken voiced concern that Russia could try to “stir the pot” between Armenia and Azerbaijan “to create a distraction from Ukraine.”

Kirby said the US was “actively engaged” in trying to help end the violence, adding that Blinken had spoken with both the president of Azerbaijan and the prime minister of Armenia.

“We’re actively engaged with both the Armenian and Azerbaijani Government to see what we can do to end this violence,” Kirby told reporters Tuesday.

CNN’s Hannah Ritchie, Philip Wang, Anna Chernova and Eleni Giokos contributed reporting, as did journalist Aren Melikyan.