Jihadis from ISIS in Mosul, Iraq
Jihadis from ISIS in Mosul, Iraq Reuters

Twenty-five Islamic State (ISIS) flags were found in Nazareth Illit, Walla! News reports Tuesday, giving further rise to concerns over the jihadist terrorist group's popularity with Arab citizens of Israel.

City employees found a bag filled with the tiny black flags on the side of a highway, according to the daily, and turned it over to the local police.

An investigation has been launched into the incident. 

News of the find surfaces just two days after an Israeli Arab teacher was sentenced to one week of house arrest and a 5,000 shekel (approximately $1,350) fine for possessing ISIS materials.

Both the teacher, 24-year-old Saladin Mahmeed, and his legal representation, insisted after the ruling that the materials are simply "Islamic textbooks" and "Muslim symbols" and that the trial was a "setup by Israel and the Shin Bet (Israeli Security Agency)." 

Mahmeed was not the first to be arrested for involvement with ISIS, however; last month, an Umm Al-Fahm resident was convicted for exiting the country and joining the terror group in Syria. 

Concerns over ISIS's influence in Israel were raised over the summer, after members of the terrorist group released a video showing how they took part in the recent war against Israel in Gaza. At least one former ISIS jihadist was killed in the Gaza fighting.

There has also been an alarming amount of support for the group among regular Arab citizens of Israel, including some flying ISIS flags and posting praise for the group on Facebook and other social media sites.