Delicate ceasefire
The Syrian military said it viewed the strike as evidence the United States and the coalition support ISIS. It called the incident a serious and blatant aggression, SANA reported.
Russia's Foreign Ministry had similar words, according to spokeswoman Maria Zakharova. She said Russia had concluded the White House is defending to ISIS. She also said that the United States didn't communicate its intention to carry out operations in the area.
The latest ceasefire has offered some respite from violence in the civil war, which has killed an estimated 430,000 people since 2011 and touched off an international refugee crisis. But there have been reports of violations, and both the Russians and Americans have said the other party is not fulfilling its obligations.
The main focus of the ceasefire was to allow humanitarian aid to reach the Syrian people besieged by war. Once the humanitarian relief was in, the Russians and Americans were meant to agree on targeting jihadist factions: Jabhat Fateh Al-Sham, the former al Qaeda affiliate in Syria, and ISIS. To do that, they are supposed to set up a Joint Implementation Center.
CNN military analyst Lt. Col. Rick Francona said it is not clear now what will happen.
"This might put in danger this Joint Implementation Center that the US and the Russians are supposed to set up in the next few days to coordinate just these kinds of strikes against ISIS and to prevent just what happened," he said Saturday.
CNN's Richard Roth, Frederik Pleitgen, Matthew Chance, Daniel Nikbakht, Merieme Arif, Mohammed Tawfeeq and Sebastian Shukla contributed to this report.