A Russian cargo plane crashed after landing on Russia’s airbase in Turkey on Tuesday, killing all 39 people on board. The Russian military blamed the crash on a technical error.

A full investigation is being conducted.

The aircraft tried to land at the air base in northern Syria before crashing to the ground Tuesday afternoon.

According to the Russian Defense Ministry, all the passengers killed on board were Russian servicemen.

As an ally to Syrian President Bashar al-Assad, Russia leases the Hemeimeem military base in Syria, near the Mediterranean coast.

Hemeimeem is Russia’s main military base for air strikes on rebel groups in Syria.

Russian President Vladimir Putin expressed his condolences towards the families of those who were killed in the crash after receiving a briefing by Defense Minister Sergei Shoigu.

Prime Minister Dmitry Medvedev has stated on the government’s website that he was “deeply shaken” by the crash.

Meanwhile, a shelling has taken place near the eastern suburbs of Damascus. Dozens of people were killed over the past 24 hours.

International aid workers described dramatic scenes of rescuers pulling corpses out of the rubble of buildings. There were also children who had not seen broad daylight in days.

Pawel Krzysiek, head of communications from the Syrian branch of the International Committee of the Red Cross, said there were thousands of families in underground shelters, reluctant to eat in front of each other and children watching as aid workers pulled corpses from out of the rubble.

The mission on Monday to the area known as eastern Ghouta was cut short after the shelling continued. This violence has called future aid shipments to the surrounding region into questioning.

Monday’s aid shipment was the first to come in eastern Ghouta in weeks amid the crippling siege and government assault that has killed 800 civilians since February 18.

The U.N. said airstrikes and shelling continued as convoys were unloading supplies.

“After nearly nine hours inside, the decision was made to leave for security reasons and to avoid jeopardizing the safety of humanitarian teams on the ground,” said Jens Laerke, deputy spokesperson for the U.N.’s Office for the Coordination of Humanitarian Affairs.

Another convoy is scheduled for Thursday, but Laerke said there must be certain security measures met for this to happen.

The Russian Defense Ministry said that Tuesday’s Russian military plane crash happened 500 meters from Syria’s Hemeimeem military base. The base is far from the line of conflict but came under shelling back in December.

Russian military outposts have also come under rebel attacks, including a drone raid earlier this year involving 13 aircraft equipped with satellite navigation.

The An-26 military cargo plane on Tuesday, was the second Russian military plane crash this year. A Su-25 ground attack jet was struck by a defense missile last month over the northern Idlib province.