"They were not injured by any kind of conventional arms," a Turkish source with access to government findings told CNN.
On Thursday, Turkish Prime Minister Recep Tayyip Erdogan told NBC News "[it] is clear the regime [of President Bashar Assad] has used chemical weapons."
"There are patients who are brought to our hospitals who were wounded by these chemical weapons," Erdogan said.
The Syrian government and rebels have accused each other of using chemical weapons in the past, prompting the United Nations to send investigators to the country in the throes of a two-year civil war that has killed an estimated 70,000 people.
U.S. President Obama has said use of chemical weapons would be a "red line" that would draw a U.S. response.
More than 190,000 Syrian refugees are living in state-run camps Turkey. Many more Syrians have fled across the border and have sought shelter in Turkish cities and towns.
Turkey also has played a major role in providing assistance and a relatively safe base for operations to Syrian opposition groups.