The US believes that the air strike that attacked Syria's aid convoy on Monday was from Russia's two warplanes. The aid convoy was reportedly hit Monday night in the area of Urum al-Kubra, west of Aleppo.

One of the US officials said that all the evidences point out to Russia being responsible fo the incident. CNN reported that Deputy National Security Adviser Ben Rhodes said that all of the information indicates clearly that the incident was an airstrike, which means there only could have been two entities responsible.

Rhodes added, "We hold the Russian government responsible for airstrikes in this airspace given their commitment under the cessation of hostilities was to ground air operations where humanitarian assistance was flowing."

According to BBC, there is one unconfirmed report which stated that 12 people were killed in the attack. A UN spokesman said that at least 18 of the 31 trucks that were initially prepared to deliver aid across the city have been hit.

"Those who bomb the aid convoys are cowards."

UN Secretary-General Ban Ki-moon called the attack "sickening, savage and apparently deliberate." He added, "Just when we think it cannot get any worse, the power of depravity sinks lower. The United Nations has been forced to suspend aid convoys as a result of this outrage. The humanitarians delivering life-saving aid were heroes. Those who bombed them were cowards."

It has been a great concern for humanitarian agencies that hundreds of thousands of civilians have been short of water, food and medicine. The attack has forced the UN to halt its aid operations in Syria.

Russia denies involvement.

Meanwhile, the Russian government denies any involvement from the incident. According to reports, it believed that the struck that attacked the convoy was not from the air but from the ground that caught fire.