MOSCOW (Reuters) - President Vladimir Putin on Thursday honored a Russian soldier killed in Russia’s military operation in Syria, breaking four months of official silence about his death.

A view shows the grave of Russian serviceman Fyodor Zhuravlyov after the funeral at a cemetery in the village of Paltso, Bryansk region, Russia, November 24, 2015. REUTERS/Maria Tsvetkova

By paying tribute to 27-year-old Fyodor Zhuravlyov, Putin tacitly raised the death toll for Russian servicemen in the five-month Syria operation to five. Russian officials previously only acknowledged four deaths.

Putin this week ordered the withdrawal of the bulk of Russia’s forces from Syria, saying they had successfully fulfilled most of their objectives. Air force pilots were welcomed back at bases in Russia to brass bands and congratulatory speeches.

The Kremlin has been able to present the mission in Syria as a success in part because Russian military casualties were low. But questions linger about whether the casualty numbers are accurate, and about other costs of the campaign.

At a ceremony in the Kremlin to award medals to servicemen returning from Syria, Putin paid tribute to those who died, and mentioned the names of their widows, who had been invited to the ceremony.

Among the names he listed was Yulia Zhuravlyova - the same family name as Fyodor Zhuravlyov, a soldier who, according to interviews conducted by Reuters with his acquaintances, was killed in unexplained circumstances in November last year.

The endings on Russian family names change according to gender, with the letter “a” added to denote a female.

Putin also mentioned the first names of the dead soldiers, including the name Fyodor. A family friend told Reuters he recognized Fyodor Zhuravlyov’s wife on TV footage from the Kremlin.

The same family friend had previously told a Reuters reporter who attended Zhuravlyov’s funeral in the village of Paltso, in western Russia, in November that Zhuravlyov served with a special forces unit.

Contacted by Reuters, Kremlin spokesman Dmitry Peskov confirmed that the death of Fyodor Zhuravlyov was acknowledged at the ceremony. He did not give further details.

CLANDESTINE OPERATIONS

Russia has never acknowledged that its special forces were active in combat missions inside Syria, saying its military role was restricted to air strikes, training and advising Syrian forces, protecting its bases, and conducting search-and-rescue missions for downed aircrew.

At the time of Zhuravlyov’s funeral, the commander of his unit told Reuters he was killed in a counter-terrorism operation in Russia’s North Caucasus region. But there was no record of any security forces having been killed in that operation.

The Russian military at the time declined to comment about Zhuravlyov, even to confirm officially whether he had died.

At the Kremlin ceremony, Putin mentioned the names of Zhuravlyov’s widow and three other widows, whose husbands had already been listed by the military as killed in Syria. A fifth serviceman, 19-year-old Vadim Kostenko, hanged himself at his base in Syria, according to the military.

Addressing the relatives of the dead at the ceremony, Putin said: “Our comrades remained faithful to the last to their oath and to their military duty.”

“We will remember their courage and nobility, that they were real men and brave warriors,” he said.

COSTS OF CAMPAIGN

Some critics of the Russian campaign in Syria say it may have led indirectly to the deaths in a plane crash over Egypt in October of 224 people, most of them Russians.

Egyptian investigators say they believe the plane, flying to Russia from the holiday resort of Sharm -el-Sheikh, may have been brought down by a bomb. Security experts have speculated Islamist militants could have planted the bomb in retaliation for Russia’s intervention in Syria.

Deaths in clandestine military operations create a dilemma for the Russian armed forces, as well as other militaries.

The military is under pressure from the chain of command to keep the operations secret, but at the same time they have a strong tradition of publicly honoring people who died carrying out their military service.

Eight Soviet submariners died after a nuclear reactor on their vessel malfunctioned in 1961, an incident later made into the Hollywood film “K-19: The Widowmaker,” starring Harrison Ford. Surviving crew members were sworn to secrecy, and information about the incident only emerged after the collapse of Soviet rule in the 1990s. A memorial to the victims was finally erected in a Moscow cemetery in 1998.