21 people were admitted to the Al-Suqaylabiyah hospital here after a suspected chemical attack by militants who fired several shells at the city, according to local media.
The admitted people are reportedly suffering from asphyxia which is believed to be caused by the use of poisonous gas by the militants, reports Sputnik.
The city is part of a demilitarised zone which was negotiated by Russian President Vladimir Putin and his Turkish counterpart Recep Tayyip Erdogan last year.
The latest attack joins a string of others involving the use of chemical weapons in the Syrian civil war. (ANI)