Sonntagszeitung newspaper published a photograph taken of one such device in possession of anti-Damascus forces in the town of Marea, north of Aleppo, at the end of June, AFP reported.
Preliminary inquiries into the photo showed the grenade in question was made by the Bern-based arms manufacturer RUAG, and was part of a shipment made by the company to the UAE in 2003.
The Federal Department of Economic Affairs (FDEA) says 225,162 hand grenades were exported to the UAE, who signed an agreement not to re-export the munitions.
"As far as the FDEA is aware, the hand grenade ... originates from a RUAG shipment to the United Arab Emirates in 2003. At present there is no evidence that Swiss hand grenades have found their way to Syria; inquiries are ongoing, however," the government statement said.
The FDEA statement also said arms shipments from Switzerland to Syria stopped in April 1998, and raised doubt whether the photograph was taken in Syria after all.
Antje Baertschi, a spokeswoman for the State Secretariat for Economic Affairs (SECO) said as a “provisional" measure, Switzerland immediately moved to "freeze all arms export permits to the UAE."
"We took this matter seriously because something similar happened last year when a journalist covering Libya found crates of Swiss munitions in Libya,” she said.
Syria has been experiencing unrest ever since March 2011, with demonstrations being held both against and in support of President Bashar al-Assad's government.
The Syrian government says outlaws, saboteurs, and armed terrorists are the driving factor behind the unrest and deadly violence while the opposition accuses the security forces of being behind the killings.
Damascus also says that the chaos is being orchestrated from outside the country and the security forces have been given clear instructions not to harm civilians.
Switzerland has decided to suspend arms shipments to the United Arab Emirates following a report that Swiss-made hand grenades are being used by armed gangs in Syria.
The measure was taken on Wednesday after the