At least 11 people were injured, nine of them seriously when two groups of Sikh worshippers clashed with knives and handgun at a gurdwara in Vienna on Sunday, police said.
The fight erupted following a dispute over the sermon given by a priest from Shri Guru Ravidas Sabha.
Police said at least six men, one wielding a gun and the others knives, attacked the preacher as others rushed to his aid, resulting in the melee.
Police spokesman Michael Takacs said one of the attackers is in critical condition, while the wounds of the others were less serious. Five suspects have been arrested, he said.
Police said nine people were severely wounded when members of two families started shooting at each other. Five people suffered head shots and stab wounds, Austrian Press Association said in a report on its website.
It quoted a witness Jasuf Kalden as saying that the fight erupted after a dispute over the sermon, given by Guru Ravidas Sabha.
Takacs said more people might have been slightly hurt and have run outside the gurdwara before police arrived. Earlier the emergency rescue services had put the number of injured at thirty. Four ambulances and three medical helicopters transported the victims to different hospitals.
The gurdwara is located in Vienna-Rudolfsheim, the capital's 15th district.