A limousine taking nine women to a party erupted in flames, killing five of the passengers in California.

The limo caught fire at around 10pm on Saturday on one of the busiest bridges on San Francisco Bay.

Five of the women were trapped, but the four other women managed to get out after the vehicle came to a stop on the San Mateo-Hayward Bridge.

San Mateo County Coroner Robert Foucrault, who is investigating the deaths, said their badly-burned bodies were found near the partition that separates the driver from the passengers.

He said the women tried to use the window opening to escape the fast-moving fire that began in the back of the limo.

Rosita Guardiano told the San Francisco Chronicle that the woman for whom the hen party was being thrown was to be married next month.

Ms Guardiano said her daughter was one of the survivors.

Investigators have not determined what sparked the fire, but the patrol said the white stretch limo became engulfed in flames after smoke started coming out of the rear of the vehicle.

A photo taken by a witness and broadcast on KTVU-TV showed flames shooting from the back of the 1999 Lincoln Town Car.

Aerial video shot after the incident showed about one-third of the back half of the limousine had been scorched by the fire.

Its taillights and bumper were gone and it appeared to be resting on its rims, but the remainder of the vehicle didn't appear to be damaged.

The driver of the limo, Orville Brown, 46, of San Jose was the only person to escape unhurt.

It was not clear how he managed to escape without injury. Investigators yesterday afternoon were still seeking witnesses.

All five women were pronounced dead at the scene.

The company that operated the limo was identified as Limo Stop, which offers service through limousines, vans and SUVS.

Ms Guardiano said her daughter, the bride-to-be, 42-year-old Mary Grace Guardiano of Alameda was being treated for smoke inhalation.

The three other women who escaped the fire, Jasmine Desguia, 34, of San Jose; Nelia Arrellano, 36, of Oakland; and Amalia Loyola, 48, of San Leandro, were taken to hospitals to be treated for smoke inhalation and burns, the patrol said.