Dozens of people were hurt in a chemical weapons attack committed by the Syrian army in Zita al-Gharbiyah in Homs, opposition sources said Saturday.
According to the Syrian opposition, helicopters belonging to Bashar Assad's army dropped barrels containing chlorine gas.
Similar reports were made during the past week in several areas in Syria.
The Syrian opposition posted videos that indicate on "quite a number" of wounded suffering from suffocation. They were treated using oxygen masks. This report has no confirmation from official sources.
Al-Jazeera quoted opposition sources who claimed some 100 suffered from suffocation, and that similar cases were documented at the village of Tamana al-Ghab.
A week ago, the rebels accused the Assad regime of a similar attack in Hama. The Syrian government, on its part, accused the al-Qaeda-linked Al-Nusra Front of that attack.
During the week, Al Arabiya reported that Assad's forces were using toxic gas in an attack in the Harasta area in the suburbs of Damascus. According to the report that cites opposition sources, nine people were wounded in the attack.
A video posted on YouTube shows several wounded being treated by a medics with the reporter announcing a "poison gas in Harasta."
Several days earlier, Syrian media reported on another chemical weapons attack in Zita al-Gharbiyah, in which two people were killed and some 100 more wounded.
Human rights organizations claimed that Syrian army jets dropped barrels of explosives with chemical substances in them. The explosion caused smoke, a pungent smell, suffocation and poisoning.
Syrian state television provided a different version of events, saying "we received information that terrorists from the Al-Nusra Front committed a chemical attack that caused the death of two and the injured over a hundred people suffering from suffocation."
The Syrian government warned that the Al-Nusra Front was planning to strike the Hama and Idlib areas as well.
Syrian opposition sources claimed that the Assad regime has committed 14 chemical attacks in 2014 so far. As a result of these attacks, 22 people were killed and 259 others hurt. The primary use of chemical weapons was done in Damascus and its suburbs, they said.
The Organization for the Prohibition of Chemical Weapons (OPCW) said Saturday that Syria has shipped out or destroyed approximately 80 percent of its declared chemical weapons material
Sigrid Kaag, special coordinator of the joint mission of the United Nations and the OPCW, said if the momentum was sustained, Syria should be able to meet its April 27 deadline to hand over all declared chemical agents.
"The renewed pace in movements is positive and necessary to ensure progress towards a tight deadline," Kaag said.
Assad agreed with the United States and Russia to dispose of the chemical weapons - an arsenal which Damascus had never formally acknowledged - after hundreds of people were killed in a sarin gas attack on the outskirts of the capital last August.
Washington and its Western allies said it was Assad's forces who unleashed the nerve agent, in the world's worst chemical attack in a quarter-century. The government blamed the rebel side in Syria's civil war, which is now in its fourth year.
Reuters contributed to this report.