Rockets were fired late Sunday from northern Iraq at a military base in Syria housing a US-led coalition, according to Iraqi security forces.
The anti-jihadist coalition said one of its fighter jets in Iraq had "destroyed a launcher in self-defence after reports of a failed rocket attack" near a base in northeast Syria.
"No US personnel were injured," it added in a brief statement to the media.
It is the first major attack against the coalition forces in several weeks.
It comes days after Israel reportedly responded to an Iranian attack with a drone strike on the Islamic republic, amid tensions fuelled by the Gaza war.
Iraqi forces had earlier said they launched a major search operation in the northern Nineveh province and found the vehicle used in the attack.
The statement from the Iraqi security forces accused "outlaw elements of having targeted a base of the international coalition with rockets in the heart of Syrian territory", at around 9:50 pm (1850 GMT).
The security forces burned the vehicle involved in the attack, the statement added.
Rami Abdel Rahman, director of the Syrian Observatory for Human Rights war monitor, said several rockets had been fired "from Iraqi territory at the Kharab al-Jir base", where US forces are stationed.
He accused the Islamic Resistance in Iraq, a loose alliance of Iran-backed groups, of staging the attack.
The group has claimed most of the attacks on US forces carried between mid-October and early February.
Agence France-Presse