At least 10 members of the Iranian Revolutionary Guard's Basij forces were killed overnight in an attack on a military post along the Iraqi border, Iran's semiofficial Tasnim news agency said on Saturday.

It was the latest deadly clash in a region where armed Kurdish groups seeking an independent Kurdistan are active.

"The attack by the evil rebels and terrorists against a revolutionary border post and the explosion of a munitions depot caused the martyrdom of 10 fighters," the Guard's ground forces division said in a statement.

The statement added that several attackers were also killed and vowed "merciless vengeance" on those that remained.

Hosein Khosheqbal, a provincial security official, told state television that 11 members of the Guard's voluntary Basij forces were killed during the fighting, which occurred in the Marivan area, about 600 kilometers (375 miles) west of the capital, Tehran, and just 20 kilometers from the Iraqi border.

"The latest news is that the Basij and Guards forces are in hot pursuit of the attackers," Khosheqbal said.

It was the largest number of Iranian soldiers killed in a single attack along the Iraqi border in recent years.

Read more: Revolutionary Guard declares 'end of sedition'

Merciless vengeance

Several armed Kurdish groups operate in the area, including the Party of Free Life for Kurdistan (PJAK), which seeks autonomy for Iran's Kurds. The group is also tied to Turkey's militant Kurdish Workers' Party (PKK), which is active in the border region.

The Revolutionary Guard said it killed three militants near the Iraqi border earlier this month and nine militants further north last month.

Iran and Iraq have failed to coordinate security efforts along the border, resulting in a porous frontier that has also been used by "Islamic State" (IS) militants to enter Iran.

Iranian Intelligence Minister Mahmoud Alavi announced earlier in the week that security forces had arrested four IS suspects in the southwest of the country. They were believed to be planning attacks.

Read more: Iran test fires ballistic missile

IS militants carried out coordinated attacks in June 2017 on the Iranian parliament building in Tehran and the mausoleum of Iranian revolutionary leader Ayatollah Ruhollah Khomeini south of the capital. At least 18 people were killed in the attacks.

Read more: What is Iran's Revolutonary Guard

bik/tj (Reuters, AFP, AP)

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