Human Rights Watch (HRW) said on Wednesday that Azeri forces appear to have deliberately bombed a Christian church in the Nagorno-Karabakh town of Shushi during recent fighting over the breakaway territory between Azerbaijan and Armenia.

Armenia accused Azerbaijan of shelling the historic Ghazanchetsots Cathedral, located on a strategic clifftop in Shushi, on October 8. The intentional targeting of a civilian building, such as a church, is considered a violation of the laws of war.

“Two separate attacks, hours apart, on the Ghazanchetsots Cathedral on October 8 in the town of Shushi, also known as Shusha, suggest that the church, a civilian object with cultural significance, was an intentional target despite the absence of evidence that it was used for military purposes,” HRW said in a statement on December 16.

The human rights organization says it collected weapon remnants at the site that “corroborate the use of guided munitions.”

“The two strikes on the church, the second one while journalists and other civilians had gathered at the site, appear to be deliberate,” HRW director for Europe and Central Asia Hugh Williamson said.

Azerbaijan President Ilham Aliyev told the BBC on November 9 that the church could have been targeted “by mistake only because … the church was not among military targets.”

“Either it was a mistake of our artillery or it was a deliberate provocation by Armenians themselves,” Aliyev said.

Azeri forces shelled the 19th-century cathedral, which is part of the Armenian Apostolic Church, during fighting between Armenia and Azerbaijan over Nagorno-Karabakh, which ended in a Russia-brokered ceasefire on November 9. The attack took place while Armenian forces still controlled Shushi. Azeri forces have since regained control over the city through territorial concessions Yerevan made to Baku under the terms of the peace deal.

Ethnic Armenian separatists have ruled over Nagorno-Karabakh since they seized the region after the fall of the Soviet Union in 1991. The breakaway territory legally belongs to Azerbaijan.

“International human rights groups have urged both Azerbaijan and Armenia to urgently conduct investigations into war crimes allegedly committed by both sides during the six weeks of fighting over Nagorno-Karabakh,” which began on September 27, Radio Free Europe/Radio Liberty reported on Wednesday.

Amnesty International said on December 10 that it has analyzed 22 videos allegedly depicting “extrajudicial executions, the mistreatment of prisoners of war and other captives, and desecration of the dead bodies of enemy soldiers” by both sides.

“During the recent Nagorno-Karabakh fighting, members of the military on both sides have behaved horrendously, displaying a complete disregard for the rules of war,” Amnesty International Research Director for Eastern Europe and Central Asia Denis Krivosheev said in a statement.

“The depravity and lack of humanity captured in these videos shows the deliberate intention to cause ultimate harm and humiliation to victims, in clear violation of international humanitarian law,” he added.