As the Turkish offensive in northern Syria against the Syrian Kurdish militant group YPG entered its fifth day, two major developments may change the course of events.

First came an announcement by U.S. Defense Secretary Mark Esper that the U.S. will be pulling out about 1,000 U.S. troops from the region, saying: "We have American forces likely caught between two opposing advancing armies and it's a very untenable situation. So I spoke with the President last night after discussions with the rest of the national security team and he directed that we begin a deliberate withdrawal of forces from northern Syria."

This only paves the way for Turkey to move forward with less obstacles.

Yet Esper also added that the Syrian Kurdish group appeared ready to cut a deal with the Syrian government and Russians to counter Turkey's advances.

Soon after, Syrian state media reported Syrian troops were moving toward northern Syria to confront Turkish forces. It's not clear if Syrian government troops would clash with Turkish forces – but it certainly creates a risky situation.

Several different military forces and rebel groups might soon find themselves in close proximity to each other.

On Sunday, Turkish President Recep Tayyip Erdogan was furious at the suggestion of some foreign leaders that Turkey would negotiate with the YPG.

Erdogan said: "Those who have sought to mediate between us and the terrorist organization. What kind of prime minister, what kind of head of state are they? It's not possible to understand. When do you see a state sit at a table with a terrorist organization?"

Ankara might consider negotiating with Damascus – but no such option has been expressed by Turkish officials yet.

By Sunday, there were losses on both sides of the border.

The Syrian Observatory for Human Rights said dozens of people have been killed inside Syria since the operation began, and humanitarian organizations reported over a hundred thousand people have been displaced.

Meanwhile, Turkish towns were also under attack again on Sunday; Erdogan stated that over 650 mortar shells and rockets have hit the Turkish cities of Mardin, Sirnak, Sanliurfa and Gaziantep since the operation began. 

As of October 13, 18 civilians were killed in Turkey due to these attacks from Syria according to Turkey's state-run news agency.

The impact on civilians has been a major concern for the international community and one of the main challenges for the Turkish military as they advanced into Syrian border towns.

Ahmed Hamada, a former colonel from the Syrian government who's now working as a military analyst in Istanbul, said that the YPG has the advantage of being fortified in Syrian towns and has also obtained sophisticated weapons such as anti-tank guided missiles, making them stronger. 

The Kurdish-led Syrian Democratic Forces have reportedly been using strategic defensive techniques such as burning tires to block visibility. But Hamada said it is a very old technique that has been used to block old jet fighters. "The modern ones instead rely more on advanced technologies and have previously determined targets, so they can carry out attacks without the need for the pilot to have visuals."

Meanwhile, the most challenging issue Turkey is expected to face in Syria may be against an enemy it has been fighting for several years now – the ISIL militants. 

Following a phone call with President Erdogan on October 6, U.S. President Donald Trump declared Ankara would take over the responsibility of over 10,000 ISIL prisoners that are being held in northeastern Syria.

Turkey's allies, including Russia, the U.S. and NATO have all expressed concerns that the operation will create opportunities for ISIL prisoners to escape.

On Sunday, Kurdish officials in Syria claimed over 750 women and children with links to ISIL fled a displacement camp following a Turkish attack in the area.

Turkey has said it would be ready to take over the responsibility of ISIL prisoners. Yet details of how the transfer of control would happen have not been revealed.

It's clearly a challenging task.

Trump has said he "made clear to Turkey that if they do not meet their commitments, including the protection of religious minorities, and also watching over the ISIL prisoners that we captured, we will impose very swift, strong, and severe economic sanctions like I did with respect to my negotiations to get Pastor Brunson out."

So far, neither international condemnations nor threats of sanctions have been enough to deter Ankara from its path to establish a safe zone along its borders. It will be critical to see how the latest move by the YPG to team up with the Syrian government will impact Turkey's actions.

(Cover: Black smoke rising in Tel Abyad after terrorists burnt tires and diesel fuel to avoid being targeted by the Turkish army's aerial vehicles, October 12, 2019. /VCG Photo)