RAMADI, Iraq, April 23 (Xinhua) -- The Iraqi forces discovered a long tunnel dug by Islamic State (IS) militants in a town near the border with Syria in Iraq's western province of Anbar, a provincial police source said on Monday.

The tunnel was discovered during search operations in Karabla area near the town of al-Qaim, some 400 km west of the Iraqi capital Baghdad, the source told Xinhua on condition of anonymity.

"The tunnel stretches tens of meters under the alleys of Karabla residential part, and the troops started to bury the tunnel after searching it," the source said.

Ahmed al-Mahalawi, mayor of al-Qaim, confirmed that the troops discovered the tunnel and said "this is not the first one in al-Qaim area as several IS tunnels had been discovered before, which were used by the militants to protect themselves from airstrikes."

On Dec. 9, 2017, Abadi officially declared full liberation of Iraq from IS militants after Iraqi forces recaptured all the areas once seized by the extremist group, including the border areas and desert in western Iraq.