BAGHDAD, Jan. 23 (Xinhua) -- A local leader of Islamic State (IS) group and two of his aides were killed Tuesday in an airstrike in 's eastern province of Diyala, a provincial security source told Xinhua.

Acting on intelligence reports, the Iraqi aircraft bombarded an IS hideout in al-Khayzarana area, some 80 km northeast of the provincial capital Baquba, killing the three militants and destroying the hideout with tunnels, the source said on condition of anonymity.

Despite repeated military operations in Diyala province, remnants of IS militants were still hiding in rugged areas near the border with in eastern Diyala, as well as the sprawling areas extending from western part of the province to Himreen mountainous area.

Dozens of IS militants fled their former bases in Salahudin province and Hawijah area west of Kirkuk after the Iraqi forces cleared these areas from the extremist militants during anti-IS offensives in the past few months.

On Dec. 9, Iraqi Prime Minister Haider al-Abadi officially declared full liberation of Iraq from IS militants after Iraqi forces recaptured all the areas once seized by the extremist group.

However, small groups and individuals of IS militants are still capable of carrying out attacks against civilians and the security forces despite operations from time to time to hunt them down.