In Afghanistan, New Insurgent Group Emerges KABUL, Afghanistan - A new, more radical insurgent group has begun a campaign aimed at terrorizing both Afghan officials and moderate insurgents, according to Afghan officials. While the Taliban publicly disavowed the new group, Afghan intelligence officials depicted it as a faction of the Taliban that is "behind the current campaign of psychological and terror attacks," as one official put it. Calling itself the Mullah Dadullah Front, after a notoriously bloodthirsty Taliban commander who was killed in 2007 in a joint operation, people claiming to represent the group have in recent days sent text messages and made telephone calls to numerous members of the Afghan Parliament, threatening them with suicide attacks if they vote to ratify the strategic partnership agreement between Afghanistan and the United States. The group also claimed responsibility for the assassination of a former Taliban minister, Mullah Arsala Rahmani, this month. Mr. Rahmani, who lived under government protection in Kabul, was viewed as a potential intermediary in any future negotiations between the government and the Taliban. The emergence of a new, more extreme insurgent faction could further trouble any efforts to restart the moribund peace process in Afghanistan. The Taliban disavowed any connection with the Rahmani assassination. After the Dadullah Front claimed responsibility for it, the Taliban responded that there was no such organization affiliated with the Taliban, and suggested that the Dadullah Front had actually been created by Afghan intelligence. On Saturday, the National Directorate of Security, the Afghan intelligence service, announced in a news release that it had arrested three members of the Dadullah Front "who were busy spreading terror and launching a psychological campaign in Kabul." A spokesman, who spoke on the condition of anonymity in line with his department's policy, said the three men were arrested in Kabul after an investigation of the messages they had sent. "We believe these three men are part of a bigger network," he said. There was no way to independently verify the intelligence service's claims. The agency has often been accused of human rights violations and of using torture to obtain confessions from detainees. Although President Obama and the Afghan president, Hamid Karzai, signed the strategic partnership agreement during Mr. Obama's visit to Kabul on May 1, the Afghan government submitted the document to Parliament to ratify. It is not clear if the parliamentary vote is binding. Over the past few days, members of Parliament have received death threats in text messages signed by the Dadullah Front. Dawood Hasas, a senator from Zabul, said he received a text message demanding that he agree to vote against the strategic agreement and warning, "We are a suicide front and we wage jihad." "We want an answer in one minute," the message concluded. A minute later, Mr. Hasas said, his phone rang and the caller demanded his answer. "I told them they cannot scare me with these threatening phone calls and texts," Mr. Hasas said. They told me if that was my decision then I will have the same destiny as Arsala Rahmani. Mullah Dadullah was a commander in Helmand Province who was accused of ordering the beheading of a hostage when negotiations for the release of Taliban prisoners broke down. He is also blamed for carrying out particularly bloody massacres in Bamian Province. Some Taliban officials have said they believe that top Taliban leaders were involved in betraying Mullah Dadullah because he had become too close to Al Qaeda. If there is a group named after him now, that too may be a front for Al Qaeda, the officials suggested. Zabiullah Mujahid, a spokesman for the Taliban, said the attacks claimed by the Dadullah Group were really the work of one man. Elsewhere in Afghanistan, a suicide bomber in the Trezi district of Khost Province attacked a police post on Saturday, detonating explosives that killed three policemen as well as two children, ages 7 and 3, who had apparently had been visiting the post, according to the district governor, Amir Padishah Dawran. Habib Zahori contributed reporting from Kabul, Taimoor Shah from Kandahar, Afghanistan, and Farooq Jan Mangal from Khost, Afghanistan.