Moscow, Mar 20 (IANS/RIA Novosti): Russia has expressed its concern over the alleged use of chemical weapons by Syria's armed opposition, saying that it would lead to an escalation of the conflict.

Syria's state news agency SANA accused anti-government militants of firing a rocket containing chemical agents into a village near the northern city of Aleppo, reportedly killing at least 26 people. Around 100 people are reported to be injured.

"We are very seriously concerned by the fact that chemical weapons have fallen in the hands of the armed opposition in Syria," Russian foreign ministry said in a statement Tuesday.

Opposition forces have denied reports of the attack and instead accused the government of using chemical weapons.

More than 70,000 people have been killed since the outbreak of hostilities in Syria, according to the latest UN estimate.

About 1 million Syrians have been displaced by the fighting, with the figure expected to triple this year, the UN said this month.