PIETERMARITZBURG, South Africa (AP) _ Twelve black youths were killed and eight were seriously wounded in gun and knife fights between two groups in a black township, police said Saturday.

Those killed in the Friday night battle in the Kwashange township outside Pietermaritzburg ranged in age from 14 to 22, police said in a brief statement.

They reported the fighting began when one group attacked and set fire to a house where the other group was meeting.

''When the occupants fled from the house, shots were fired at them and they were attacked with cane knives,'' the statement said.

Police did not identify the groups involved or give any motive for the fighting. The statement said aninvestigation is under way.

Meanwhile, police said Saturday that 234 people were arrested, most for minor offenses, in a Friday night police sweep through the huge Soweto black township outside Johannesburg.

A report said among those arrested were 85 people drinking in unlicensed bars and 77 women found in all-male hostels.

The operation involved 1,400 security force personnel, according to the report.