The first death of a Russian soldier in Syria was confirmed Tuesday, with the Russian government saying it was a suicide, Reuters reported. The soldier was identified as Vadim Kostenko, 19, from Russia’s southern Krasnodar region, and his parents said they were told he hanged himself over a romantic relationship.

“I will never believe this version," said Kostenko’s mother, Svetlana. “We spoke every day by phone for half an hour. [On Saturday] he was cheerful, happy, and he laughed.” Kostenko’s father also echoed his wife’s sentiments, saying he did not believe the suicide story.

Initially, the Foreign Ministry said Tuesday that no information was available, and Russian President Vladimir Putin’s spokesman told reporters to refer their questions to the Defense Ministry. That ministry also declined to comment, AFP reported.

Russian news agency Interfax reported that the Defense Ministry later said Kostenko had “taken his own life during rest after duty,” the Financial Times reported. The official said text messages on Kostenko’s phone showed he had argued with his girlfriend.

Kostenko died Saturday, according to the Conflict Intelligence Team, a group is tracking Russian military involvement and deaths in Ukraine and Syria. Kostenko joined the military in June as a contract soldier and went to Syria with the 906th Close Air Support Regiment, the Conflict Intelligence Team reported.

Russian officials have long denied and hidden the deaths of Russian soldiers who have fought in the conflict in eastern Ukraine that began in April 2014 and has taken the lives of more than 8,000 people. Western reporters were attacked and harassed when they tried to film the secret burials of Russian soldiers killed in Ukraine. Reporting on the death of military personnel even in times of peace has been banned in Russia.

Kostenko’s family said a funeral was planned for Wednesday, but they still had not received their son’s body. Other reports of Russian military personnel deaths in Syria remain unconfirmed.

Russia has long supported the regime of Syrian President Bashar Assad. The civil war in Syria that began in 2011 has taken the lives of more than 200,000 people and displaced millions. Russia began airstrikes in Syria Sept. 30, saying they would target the Islamic State militant group, also known as ISIS, to prevent the group from attacking Russia. Approximately 2,000 Russian military personnel are taking part in operations in Syria.