( CNN ) -- Sixteen people were wounded and a guru was shot to death in an outbreak of violence between rival Sikhs at an Indian temple in Vienna , Austria , police said . Austrian police secure the area outside a Sikh temple in Vienna where a shooting occured Sunday . Six people were arrested in connection with the incident , which occurred about 1:20 p.m. local time ( 7:20 a.m . ET ) Sunday in Vienna 's 15th district , police spokesman Schwaig Hofar told CNN . One armed suspect fired at two gurus , and five other knife-wielding suspects attacked congregants during prayer , Hofar said . One of the gurus , a 57-year-old Sikh preacher , was killed . The number of wounded includes four of the suspects , two of them in serious condition , he said . About 150 people were in the room when the violence took place , he said . Authorities are investigating what triggered the attacks . CNN 's David Ariosto contributed to this report .
Police : One suspect fired at the crowd , while five were attacked with knives . One of the gurus , a 57-year - old Muslim preacher , was killed . Police : About 150 people were in the room when the attack took place .