COX S BAZAR, Bangladesh (Reuters) - For 28-year-old Rohingya Muslim shopkeeper Mohammed Rashid, the evening phone call from organizers of the fledgling insurgent movement came as a surprise.   Be ready,  was the message. A few hours later, after meeting in the darkness in an open field, he was one of 150 men who attacked a Myanmar Border Guard Police post armed with swords, homemade explosives and a few handguns. At the end of a short battle, half a dozen men he had grown up with in his village were dead.  We had no training, no weapons,  said Rashid, from the Buthidaung area of Myanmar s Rakhine state, who had joined the group just two months earlier. Accounts from some of those, like Rashid, who took part in attacks by the Arakan Rohingya Salvation Army (ARSA) on dozens of police posts early on Aug. 25 paint a picture of a rag-tag band of hopeless, angry villagers, who were promised AK-47 rifles but ended up fighting with sticks and knives. Hundreds joined as recently as June, according to the accounts, and membership meant little more than a knife and messages from leaders on the popular mobile messaging app Whatsapp.  Reuters interviewed half a dozen fighters and members of the group now sheltering in Bangladesh, as well as dozens of others among the more than half a million Rohingya refugees who have fled across the border to escape a Myanmar army counteroffensive that the United Nations has branded ethnic cleansing. ARSA, which emerged in 2016, says in press releases and video messages from its leader, Ata Ullah, that it is fighting for the rights of the Rohingya, a stateless Muslim minority that has long complained of persecution in mainly Buddhist Myanmar. Myanmar says ARSA is a ruthless Islamist extremist movement that wants to create an Islamic republic in northern Rakhine. Despite the massive suffering inflicted on their communities in the weeks since the August attacks, most of the fighters now stuck in dirt-poor camps said they were determined to continue their fight and some refugees voiced support for the insurgency. Other refugees Reuters spoke to criticized the insurgents for bringing more misery upon them. Myanmar leader Aung San Suu Kyi s spokesman, Zaw Htay, said ARSA had killed many Muslims who had cooperated with the authorities and so  people have felt threatened and terrorized  into supporting it. He added that Myanmar s intelligence showed that religious scholars were prominent in recruiting followers. ARSA denies killing civilians, and did not respond to a request for comment this week. Analysts say the violence could galvanize ARSA members and supporters huddled in the refugee camps and among those Rohingya still in Myanmar, as people feel they have even less to lose.  A militancy like this finds fertile ground because of the desperation of the community,  said Richard Horsey, a Yangon-based analyst and former U.N. official.  They are willing to take suicidal steps because they don t see any other choice.  Transnational Islamist groups could also try to exploit the desperation in the camps to radicalize people, Horsey added. Al Qaeda last month called for support for the Rohingya. Reuters could not independently verify the individual insurgents  stories, but there were broad similarities in all of their accounts. One fighter, 35-year-old Kamal Hussain from a village in Rathedaung in Myanmar s Rakhine state, said he joined ARSA when a religious teacher stood in his village square in June, during the Muslim holy month of Ramadan, and implored a crowd of hundreds to fight.   He said we have no choice but to attack Myanmar because our brothers and sisters are being killed day by day. I think everyone joined that day,  Hussain said, as he sat under a tarpaulin in a Bangladesh refugee camp.  We should attack again and again. I would go back to fight if I had the chance.  Unlike longer-serving fighters, most new joiners had little or no training or contact with the group s leaders, who communicated using Whatsapp and delivered rudimentary homemade explosives ahead of the assaults. A third fighter, his account supported by comments from two elders from his village interviewed separately, said he and about 60 men from Myin Hlut signed up three months ago.  The 26-year-old, who asked not to be named because he feared arrest by Bangladeshi authorities, said he was among 200 men who attacked another police checkpost in the early hours of Aug. 25.  We had only knives and sticks, no guns,  he said.  They promised us AK-47s but we got nothing. The explosives didn t work. We had two of them for the whole group, but when we threw them nothing happened.  About 40 fighters were killed, he said, but added that he would do it again if called on.  I still support ARSA,  he said.  If my leaders call me to go again and fight, I will go back.  According to two village-level commanders, there were Whatsapp groups restricted to leaders and others to members. Bigger groups, administered from overseas, were used to build broader community support for ARSA and the Rohingya cause.  On his phone, Shoket Ullah, an uncle of the 26-year-old fighter, scrolled through messages posted in the Whatsapp group  ARSA.G1 , administered through a Saudi phone number, where ARSA press releases, videos of alleged Myanmar military violence and messages of support for Rohingyas were shared. Another Whatsapp group on Ullah s phone,  Rohingya Desh Arakan , is administered by someone using a number from Malaysia. Tens of thousands of Rohingya live in both Saudi Arabia and Malaysia. Rohingya anger at Myanmar has long existed, but this is the first serious armed resistance in decades.  In the crowded Bangladeshi camps, several refugees voice support for ARSA.  I am disappointed and regret what happened but this was pre-planned by the Myanmar government,  said Shafi Rahman, a 45-year-old Burmese teacher whose village was burned to the ground the day after the attacks.  If ARSA didn t attack, they would have done this to us anyway.  Several refugees said some people had begun to sell cattle, vegetables and rice to raise funds for ARSA. Not everyone was supportive, however. When Kamal Hussain, the fighter, argued that ARSA needed to keep fighting, his neighbors in the camp shouted him down.  We have lost everything. Violence is not the answer,  shouted one elderly man, as muddy water spilled into the tent he now calls home.    It is not obvious how fighters would regroup and rebuild after so many have fled across the border or disappeared.  Three of the fighters who spoke to Reuters said they had been surprised by the ferocity of the Myanmar military s response, and within weeks commanders had told their men to put down their weapons and abandon their villages. Several said Whatsapp groups where regional and field commanders from ARSA, which before a rebranding this year called itself al-Yakin, or  Faith Movement , would post updates had gone quiet.   People who blame this on al-Yakin need to realize my people had to flee in 1978 and in the 1990s when there was no ARSA,  said one of the two village-level commanders, who grew up in Bangladesh after his family fled an earlier outbreak of violence, but returned to Myanmar in the 1990s.  We should continue to attack. Even women can join.  