US and Iraqi forces arrested Muslim cleric Abd al-Sattar Abd al-Jabbar of the AMS, two of his sons and a neighbour in the Tunis neighborhood of Baghdad early on Friday morning, Aljazeera reported.
"We think this is a dangerous development. Sheikh abdul-Jabar is a prominent figure. This is waging war against the Association of Muslim Scholars," said AMS spokesman Bashar Muhammad al-Faydhi.
Several hours earlier, the head of the AMS office in Kubeisa in western Iraq was arrested along with four other members. They were on their way back from Baghdad when US forces stopped their convoy and arrested them.
The AMS had organised the gathering in Baghdad on Wednesday to discuss the US military offensive against Falluja and other Iraqi towns.
Dozens of Iraqi Muslim scholars and clerics attended Wednesday's meeting, which they said was held at the request of residents of Falluja.
A delegation from Falluja blamed the interim Iraqi government for driving the negotiations to a deadlock.
A people's spokesman said delegates from Falluja offered all manner of possible solutions to the crisis, but the negotiations collapsed when interim Iraqi prime minister Iyad Allawi threatened to storm the town unless it handed over the Jordanian fugitive, Abu Musab al-Zarqawi.
Right to resist
The conference issued a final statement blaming the demoralisation of Arab and Muslim populations on their governments, who it said did not act to aid the Arab Muslim people in Iraq.
Resistance fighters in Falluja have
vowed to resist any invasion
Participants agreed that the Iraqi people are exercising one of their legitimate rights by resisting military occupation. The statement confirmed the right of resistance and held Allawi's government responsible for "US massacres in Iraq".
The statement said that in case Falluja came under military attack, Iraqis should boycott the election due next January. It said the election would be illegitimate if it was carried out while an Iraqi city was being shelled.
Appeal to UN
The spokesman described Allawi's demand as impossible to meet, on the grounds that Falluja residents knew nothing about al-Zarqawi's whereabouts. He went on to give a detailed report on the town's civilian casualties.
Participants in the AMS conference called on the UN's secretary-general and Security Council members to fulfil their responsibilities and condemn the "US aggression" on Falluja.
They demanded that an international delegation be sent to investigate the "genocide" being perpetrated by the US Army in Iraq on a daily basis.
The statement expressed surprise at the silence of Arab League and Islamic countries, and called on Arab and Muslim states to take action to stop the "daily killing campaign" against the Iraqi people.