At least 11 people were wounded, several severely, in an armed attack involving rival Sikh groups Sunday morning in a temple in the Austrian capital Vienna, according to dpa. According to the APA news agency, the incident took place during a sermon by two guest gurus from India. One of them, Sant Niranjan Dass, was among the wounded, hit by two bullets. According to witnesses, several bearded and turbaned men equipped with at least one firearm stormed the temple during sermons by the guest speakers. The attack triggered panic among the congregation of at least 150 - some reports spoke of 350 - in which few of the men wore the traditional untrimmed beard and long hair woven into a turban that is typical Sikhism practice. "Suddenly they took a gun and shot directly at the preachers," said one woman present. "The people - children and everyone else - ran out. They ran for their lives." During the melee, members of the congregation pounced upon the attackers and overpowered them, beating some severely. The visiting gurus, both of whom were severely wounded, had be previously guests at the temple, which was first opened in 2005. Though having many followers in India, the two were rejected as heterodox by a rival Vienna Sikh community. Police believe the conflict was based on doctrinal differences between the more traditional Sikh community and the liberal group whose temple was the scene of the attack.