Turkish Defense Minister Hulusi Akar claimed on Wednesday that Turkey's military had hit nearly 500 Kurdish targets across Iraq and Syria as part of a campaign of airstrikes.

"So far 471 targets have been struck and 254 terrorists were neutralised in the operation," Akar was quoted as saying by the official Anadolu news agency.

Ankara began the series of airstrikes as part of the "Operation Claw-Sword" offensive on Sunday.

Turkish President Recep Tayyip Erdogan threatened on Tuesday to launch a ground operation into Syria "with tanks and soldiers" in defiance of international pressure not to do so. 

Turkey's airstrikes followed a bombing in Istanbul on November 13 that killed six people and wounded 81. Ankara blamed the attack on the Kurdistan Workers' Party (PKK), which is blacklisted as a terror group by the European Union and the United States.

On its part, the PKK denied any role in the bombing -- the deadliest in five years after a spate of attacks in Turkey between 2015 and 2017.

In the same context, Al Mayadeen sources in Al-Hasakah reported that the Turkish army shelled positions belonging to the so-called Syrian Democratic Forces (SDF) in the vicinity of Amuda, Al-Qahtaniyah, and Al-Qamishli in Al-Hasakah governorate, reporting casualties as a result of the shelling.

The sources added that the Turkish shelling caused great damage to a number of facilities that the SDF take as their headquarters, with a fire breaking out in one of the oil wells in Al-Qahtaniya countryside, northeast of Al-Hasakah.

Al Mayadeen correspondent also reported that a Turkish drone targeted a gas plant in Jal Agha area, east of Al-Qamishli.

In addition, the Turkish warplanes launched four airstrikes on the village of Ali Agha in Tel Kochar, northeastern Syria, and reports of casualties were recorded. 

This coincided with the Turkish air force targeting the vicinity of the Cirkin prison in Al-Qamishli for ISIS prisoners.

US says Turkey’s operation in Syria 'to complicate fight against ISIS'

In a first, Turkish drones targeted on Tuesday a joint base belonging to the "International Coalition" and the SDF in the western Al-Hasakah Dam, killing two Kurdish militants and wounding three others.

Al Mayadeen sources confirmed that the bombing targeted the headquarters of the SDF Special Forces a few meters away from the headquarters of the US occupation base in the Life Stone resort and the residence of the Commander-in-Chief of the SDF, Mazloum Abdi. 

The sources pointed out that the Kurdish forces requested an immediate meeting with the Americans to discuss this development.

On his part, White House National Security Council Strategic Communications Coordinator, John Kirby, claimed that the US is concerned that Turkey's counter-terrorism campaign in northern Syria could "complicate the war against ISIS."

During a press briefing, Kirby said, "Turkey does continue to suffer a legitimate terrorist threat, particularly to their south. They certainly have every right to defend themselves and their citizens. What concerns us about cross-border operations remains the same… that it might force a reaction by some of our SDF partners that would limit and constrain their ability to continue to fight against ISIS [Islamic State]."

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