BAGHDAD, March 13 -- A total of 26 members of Iraqi security forces were killed and 72 others wounded in clashes with Islamic State (IS) militants Friday in northern Iraq, security sources said.

A security source told Xinhua that Iraqi forces on Friday continued their offensive in Tikrit, the capital city of Salahudin province.

Three members of security forces were killed and four others wounded in clashes with the IS militants near the Tikrit hospital, as well as six forces were killed and 11 wounded in a suicide bomb attack in western part of the city.

Dozens of militants were killed in the battles, but the exact number is unknown temporarily.

The source said that the IS militants launched an attack near a highway in southwest of Samarra, the second largest city of Salahuddin province, but foiled by the security forces.

Eight security forces and nine extremist militants were killed in the clashes, and other 14 soldiers injured.

The sources added that nine members of the Iraqi Kurdish forces were killed and 53 others were injured in the clashes with IS militants in southwest of Kirkuk, some 250 km from Baghdad, when they surrounded and tried to free some villages occupied by IS.

Some 30,000 Iraqi troops and thousands of allied Shiite and Sunni militias have been involved in a week-long offensive to recapture Tikrit and other key towns and villages in northern part of the Salahudin province from IS militants.

Large parts of the province have been under IS control since June 2014 after bloody clashes broke out between Iraqi security forces and the IS group.

The militant group has taken control of the country's northern city of Mosul and later seized swathes of territories in Nineveh and other predominantly Sunni provinces.