By Caroline Wyatt BBC correspondent in Kabul

Afghanistan's Foreign Minister Dr Abdullah Abdullah has said the 160 people still being questioned on suspicion of planning attacks in Kabul were not plotting a coup against the interim government.

But he described their activities as an attempt to destabilise the current security situation.

Afghanistan's interim government is now trying to play down talk of a coup, which was sparked by mass arrests earlier this week.

More than 300 people were arrested on suspicion of plotting to kill the interim leader, Hamid Karzai, and the former king, Zahir Shah.

Afghan security sources immediately blamed the warlord and radical Islamic leader Gulbuddin Hekmatyar.

'Conclusive evidence'

Dr Abdullah said the evidence found was conclusive, including documents stamped with the seal of the Hezb-i-Islami - a radical Islamic party headed by Gulbuddin Hekmatyar, a fundamentalist Muslim leader.

Gulbuddin Hekmatyar: Leader of a Pashtun-dominated Islamist group

However Dr Abdullah added that no single ethnic or political group was responsible.

He said the government had won popular support within Afghanistan, but that it did have enemies - among them, those who had not gained the influence they had hoped for.

Dr Abdullah said journalists would be shown the evidence once the investigation was further advanced.

"The investigations are still continuing, the evidence is very clear evidence, undeniable evidence, like equipment and devices which could only be used for sabotage activities or terrorist actions," said Dr Abdullah.

"But what is also worth mentioning is that this issue is just a security incident. It is not of a political or ethnic nature."

Warlord

The man most people blame for the incident, Gulbuddin Hekmatyar, was one of Afghanistan's most blood-thirsty warlords in the fight against the Soviet invasion.

He then turned his guns on other Afghan factions during the civil war, destroying large parts of Kabul and killing thousands of civilians.

Mr Hekmatyar fled to Iran when the Taleban took power, but he is believed to be back in Afghanistan after Iran closed his offices for making threats against the interim Afghan government.