The world's chemical watchdog has denied a report by the Syrian government that investigators and their drivers had been kidnapped on a fact-finding mission.

The Organisation for the Prohibition of Chemical Weapons said the group was "safe" and returning to base after an attack.

"All team members are safe and well and heading back to their operating base," said OPCW spokesman Michael Luhan.

The Syrian Foreign Ministry had earlier said the group was kidnapped in the province of Hama.

The team are investigating allegations that Syrian government forces used chlorine on a rebel-held village in Hama last month.

The OPCW said late last month that it would deploy a fact-finding mission to investigate the allegation that the Syrian government had used chlorine as a weapon in breach of its commitments under the Chemical Weapons Convention.

The Syrian government signed the convention last year as part of a Russian and US-brokered deal under which it pledged to destroy all of its chemical weapons.

Syria was not required to declare its stockpile of chlorine, which is a toxic but weak agent, as it is widely used for commercial and domestic purposes.

But its use for military purposes would still be a breach of its undertakings under the convention.