Syrian Democratic Forces fighters inspect a tunnel dug by ISIS inside a house in the Raqqa’s al-Sanaa industrial neighbourhood.

:: Fighters of the Kurdish People’s Protection Unit (YPG) said that they found tunnels used by ISIS, after seizing the western side of Raqqa.

According to the fighters of Kurdish YPG, the tunnels were found in residential buildings and connected houses where ISIS members stored weapons and protected themselves from air strikes launched by the Military intervention against ISIS.

The Syrian Democratic Forces said on Monday that they seized a new neighborhood in Qadisiyah district, west of Raqqa.

The lack of rapid progress is due to ISIS’s intensification of attacks, the Syrian observatory quoted a source on Sunday.

Earlier in June, the fighters of the Syrian Democratic Forces started attacking Raqqa that ISIS seized in 2014 transforming it into the de facto Syrian capital of its self-declared “caliphate.”