The US troops in the vicinity of the city of Kobani came under artillery fire from Turkish positions at approximately 9 p.m. on Friday, Xinhua news agency quoted the statement as saying.
"The explosion occurred within a few hundred meters of a location... in an area known by the Turks to have US forces present," it said.
"All US troops are accounted for with no injuries. U.S. forces have not withdrawn from Kobani.
"The US demands that Turkey avoid actions that could result in immediate defensive action," the statement added.
Secretary of Defence Mark Esper said earlier in the day that he had expressed strong opposition to Ankara's actions in Syria to his Turkish counterpart Hulusi Akar, reiterating that the offensive caused damage to bilateral relationship.
Esper also made clear to Akar that the Turkish offensive risked serious consequences for Turkey, but the Pentagon chief did not elaborate.
Treasury Secretary Steven Mnuchin said on the same day that President Donald Trump would give the Treasury authority to designate individuals and entities of the Turkish government involved in human rights abuses or actions leading to the further deterioration of peace, security and stability in northeast Syria.
"We can shut down the Turkish economy if we need to," Mnuchin said in a briefing at the White House.
Turkish Foreign Minister Mevlut Cavusoglu on Thursday said that Turkey would retaliate if the US imposed sanctions over its offensive into northeast Syria, according to media reports.
On Wednesday, Turkey launched military operations targeting the Kurdish forces in several parts of northeast Syria after the US started pulling its troops out of there following a recent decision.
( With inputs from IANS )