The United Nations has accused the Syrian regime of committing a massacre in Idlib for three months, asking Russia to provide explanations, and announced the dispatch of a convoy of humanitarian aid to the city, while several wounded on Tuesday after the bombing in northern Syria.

UN Under-Secretary-General for Humanitarian Affairs, Mark Lokoc, said the bombing of the Syrian regime, backed by Russia for more than 90 days, had triggered a massacre in the "reduction zone" of Idlib.

He added that he was still hoping for further clarification from Russia on how to use the details provided to the UN mechanism to avoid a clash in Syria. Hospitals and schools were targeted, although the United Nations provided details of its coordinates to prevent the targeting of the Russian side.

Al-Jazeera correspondent Mohammed al-Alami said that Lukok presented a very bleak picture of the situation in Syria, where he talked about the deaths of 450 people in three months and the displacement of half a million Syrians.

According to the correspondent, Lokoc seemed frustrated that there had been no progress on the humanitarian level, supported by delegates to the Security Council, while the Russian delegate insisted on justification of the bombing claiming to target "terrorists".

Meanwhile, a UN statement said 19 truckloads of humanitarian aid crossed from the Turkish province of Hatay to Syria for distribution to needy people in the city of Idlib and its countryside.

Russian and Syrian aircraft and artillery continued to bomb Khan Sheikun, Ma'arrah al-Nu'man, Sarqib and other towns in rural Idlib, and the towns of al-Barqum, al-Boabiya, Khalza, the ICARDA district in the countryside of Aleppo, and the towns of Kafr Zeita, Altamneh and Murek in the Hama countryside.

The network added that the opposition factions opposed the attempt to make new advances to the regime forces in the mountain Kurds in Lattakia province, amid aerial bombardment, confirming the deaths and injuries in the ranks of two groups of elite forces of the regime.