Afghan security forces on Thursday (May 30) said they arrested six suspected militants believed to be planning an attack on the government, after an anti-insurgency operation in Kabul.

They added that one suspected insurgent was killed in the operation on Wednesday (May 29) night.

At a news conference on Thursday, spokesman to the National Directory of Security, Shafiqullah Tahiri, said they believed the suspected militants had connections to Pakistan's Inter-Services Intelligence (ISI) network.

If, as alleged, the ISI has ties to the Afghan Taliban and other insurgent groups fighting U.S.-led NATO troops in Afghanistan, it may be able to bring them to the negotiating table - though Pakistan denies having ties to militant groups.

The alleged connection of these six with the ISI will put a further strain on already tense relations between Afghanistan and Pakistan.

Afghanistan has long been suspicious of Pakistani intentions, accusing Islamabad of backing insurgent groups to further its own interests.

Pakistan's government denies supporting or giving sanctuary to insurgents on its territory and has said it would do what it can to advance the Afghan reconciliation process.

Pakistan is seen as vital in bringing stability to Afghanistan after most foreign troops prepare to withdraw by the end of next year.

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