An airstrike by U.S.-led coalition forces has killed at least six Nusra Front fighters operating from a base in the northern Syrian city of Aleppo, Reuters reported Thursday.

The news agency cited information from the Britain-based Syrian Observatory for Human Rights, which has been monitoring the ongoing conflict in Syria. The Observatory said overnight airstrikes by a U.S.-led coalition shifted off the Islamic State group, instead targeting the al-Qaida-affiliated Nusra Front and another militant group. That second hard-line Islamist group is Ahrar al-Sham.

The Observatory said attacks from Wednesday to Thursday hit the Nusra Front in northwestern Syria’s Idlib province. The airstrikes mark only the second time the al-Qaida-linked rebels have been targeted since the anti-Islamic State attacks began in September.

Reuters provided minimal details about the deadly attack on the Nusra Front.

Earlier, it had reported that a strike targeted a car used by Nusra commanders in the Idlib town of Sarmada near the Turkish border, according to residents. The news agency, which said the vehicle reportedly was carrying ammunition, did not indicate whether anyone was injured.

But Reuters reported that residents of neighboring Harem said an airstrike had killed at least four children and injured dozens. The residents blamed the coalition for the strike.

Nusra Front bested Western-backed moderate rebels in the same area last week.

The first strikes against Nusra Front in September targeted a militant cell that the United States called the Khorasan group, alleging the militants had “imminent” plans to attack Western targets.

Strike near border

The Observatory also reported early Thursday that Ahrar al-Sham was hit for the first time near the northwest Bab al-Hawa crossing along the Turkish  border.

Daily coalition airstrikes have largely focused on Islamic State targets in northern and eastern Syria.

A fractured Syria, already in a three-year civil war, faces an encroaching Islamic State group as the ultra-radical Islamist group fights to expand its reach through Syria and Iraq.

Iraqi television station showed footage late Wednesday of government forces fighting IS militants in the restive city of Beiji, north of Baghdad. The city is home to Iraq’s largest oil refinery, which has been under militant control since June.

  airstrikes, conflict, nusra, syria