ANKARA, Turkey — Turkish warplanes carried out airstrikes on Tuesday against suspected Kurdish rebel positions in northern Iraq and in northeastern Syria, the military said, in a bid to prevent militants from smuggling fighters and weapons into Turkey.

The attack killed at least 18 U.S.-allied Syrian Kurdish troops, according to a monitoring group, as well as five members of the Iraqi Kurdish militia known as the peshmerga and drew swift condemnation from Baghdad.

Syrian Kurdish forces said the strikes hit a media center, a local radio station, a communication headquarters and some military posts, killing an undetermined number of fighters in Syria's northeastern Hassakeh province. The Britain-based Syrian Observatory for Human Rights, which monitors the Syrian war, also reported the strikes on the media and military targets in Karachok.

According to the Observatory, the airstrikes killed 18 members of the Syrian Kurdish militia known as the People's Protection Units, or YPG. The Observatory had earlier said only three were killed. Kurdish officials were not immediately available for comment.

Ankara says members of the outlawed Kurdistan Workers' Party, or PKK, are finding sanctuaries in neighboring Iraq and Syria, among those countries' own Kurdish minorities.

A Turkish military statement said the pre-dawn strikes hit targets on the Sinjar Mountain in northern Iraq and also in a mountainous region in Syria. It said the operations were conducted to prevent infiltration of Kurdish rebels, weapons, ammunition and explosives from those areas into Turkey.

A Turkish security official, speaking on condition of anonymity in line with Turkish government protocol, said the airstrikes are believed to have killed around 200 PKK militants, including some senior commanders. The claim could not be independently confirmed.

Iraq's Foreign Ministry denounced the strikes as a "violation against Iraq's sovereignty" and called on the international community to put an end to such "interferences" by Turkey.

"Any operation that is carried out by Turkish government without any coordination with the Iraqi government is totally rejected," Foreign Ministry's spokesman, Ahmad Jamal, told The Associated Press.

He warned against a Turkish military operation in northern Iraq, saying it won't "bring a solution, but will instead complicate the issue and destabilize northern Iraq."

Although Turkey regularly carries out airstrikes against PKK targets in northern Iraq, this was the first time it has struck the Sinjar region. Turkey has long claimed that the area was becoming a hotbed for PKK rebels.

Sinjar Mayor Mahma Khalil said the strikes started at around 2:30 a.m. and killed five members of Iraqi Kurdish forces known as peshmerga, and wounded nine. Khalil said he was not aware if there were casualties among PKK troops.

The peshmerga forces' command, meanwhile, called on the PKK to withdraw from the Sinjar region, saying the "PKK must stop destabilizing and escalating tensions in the area."

Last year, Turkey sent troops into Syria to back Syrian opposition fighters in the battle against the Islamic State group and also to curb what is perceives as the territorial expansion of U.S.-backed Syrian Kurdish forces, which it claims are affiliated with the PKK. The Kurdish group, which has led an insurgency in southeast Turkey since 1984, is considered a terror organization by Turkey and its allies.

In its statement, the military vowed to press ahead with operations against the PKK both inside Turkey and across its borders until the "last terrorist is eliminated."

The Syrian Kurdish forces denounced Tuesday's strikes on their positions as "treacherous," accusing Turkey of undermining the anti-terrorism fight.

Aside from aspirations for autonomy, the Kurdish group in Syria is part of the U.S.-led international coalition against the Islamic State militants who seized large swaths of Syria and Iraq in 2014. Since then, the IS has suffered major setbacks at the hands of the coalition, losing large chunks of the territory the Sunni militant group once held. The Syrian Kurdish forces, backed by the U.S.-led coalition, are closing in on IS de facto capital, the city of Raqqa.

"By this attack, Turkey is trying to undermine Raqqa operation, give (IS) time to reorganize and put in danger lives of thousands of" displaced, the YPG said on its Twitter account.

In other developments, at least 12 people, including civilians, were killed in an airstrike in northwestern Syria's rural province of Idlib, the Observatory reported. The area is controlled by hard-line rebel factions, some associated with al-Qaida. The Observatory said it suspected a Russian jet was behind the strike.

Meanwhile, the U.S. military's regional command denied coalition aircraft had targeted Islamic State targets around the northern Syrian town of Tabqa on Monday. Local activists had said eight members of the same family were killed when a coalition aircraft hit a vehicle in which they were trying to flee the IS stronghold. The town is under siege by Syrian Kurdish forces.