US Air Force Lockheed Martin F-35B Lightning II fighter jet
A Lockheed Martin F-35B Lightning II joint strike fighter flies toward its new home at Eglin Air Force Base, Florida in this U.S. Air Force picture taken on January 11, 2011. Lockheed Martin Corp on Monday said it has delivered the next version of the computer-based logistics system used to support the F-35 fighter jet to the U.S. military for flight testing. Reuters/Stringer

The U.S.-led coalition may have to be extra careful the next time it sends out fighter planes to assist the Iraqi troops against the deadly jihadi fighters. The ISIS militants had shot down a Syrian warplane on Tuesday, according to the Britain-based Observatory for Human Rights monitoring group.

The group said it was the first time the ISIS forces has shown it has the ability and machinery to target and down fast-moving military air jets, it what could also be a stern warning to the U.S.-led coalition that it is not afraid of its airstrikes and that it could also easily avert incoming jets into its stronghold.

Rami Abdel Rahman, Observatory director, said the plane was hit while carrying out strikes on Raqa, 450km northeast of Damascus, an ISIS stronghold. He told the AFP the jet crashed onto a house in the Euphrates Valley city.

At least eight people were killed by the incident. Many people likewise immediately fled from the region, thinking it might be the next target for a U.S. airstrike.

"By God, yes, people began fleeing about a week ago," AP quoted a resident.

Just on Sunday and Monday, the U.S. made its first airstrike specifically geared towards the ISIS near Baghdad.

Read: US Has Carried Out Expanded Airstrike, Targets ISIS Near Baghdad, Destroys 6 Vehicles and One of IS Fighting Positions

The AP further said pictures of the wreckage of the supposed downed Syrian warplane were published by a militant Web site.

Still, the presence of the anti-aircraft weapon near Raqqa should not be understood that all the militants are there.

A report by Reuters said the ISIS has evacuated the buildings it used as offices. Moreover, it has moved and redeployed its heavy weaponry as well as relocated the families of the fighters out of the city.

Quoting one unidentified Raqqa resident, the terror jihadi fighters were said to be "on the move" yet maintain "sleeper cells everywhere."

"Islamic State is now carrying out tactical defensive moves by relocating their assets to different places so that their heavy weaponry is not all concentrated in one place."

Video of where the Syrian warplane crashed.

YouTube/raqqa U.M.C