Relatives and dozens of fellow Irish students have gathered at a church for a vigil remembering four of the six young people killed in the California balcony collapse.

Hearses carried the four metal coffins into St Columba Catholic Church in Oakland and about 15 of the victims' immediate family members huddled together in the rectory for about an hour before entering the church for the viewing that was limited to relatives, friends and fellow students.

A bus and a van bearing about 50 other Irish students living in the San Francisco Bay Area for the summer, as were the four victims, included students who had been at the party in Berkeley, where the balcony collapsed during a 21st birthday party early on Tuesday.

The balcony collapsed from the fifth floor of an apartment building, hurling 13 people to the street 50 feet below. Six died and seven survivors are being treated in hospitals.