Syria war: US deploys reinforcements to Syria after Russia clashes

 The U.S. has deployed 100 additional troops to north-east Syria after tensions between U.S. and Russian forces have been steadily increasing. 

Russia is backing the Syrian government, whereas the U.S. backs local Kurdish fighters. This has led to some tension between the two countries, and incidents between the two have escalated this year. 

The United States military has said Russian forces have been entering into secure zones which the U.S. has told them not to. Last August, this ended in a vehicle collision where seven U.S. troops were injured. The tension between Russia and the U.S. has not been directly addressed as of yet, however the decision to deploy more American forces into Syria is a "clear signal to Russia to adhere to mutual de-confliction processes and for Russia and other parties to avoid unprofessional, unsafe, and provocative actions in north-east Syria," according to a United States official.

https://www.bbc.com/news/world-middle-east-54215915