The Australian Navy will impose sanctions on eight sailors from the HMAS Ballarat who were involved in 2013 in hazing rites with sex assault. Some of them are in danger of being kicked out of service, said the Ministry of Defence in a statement.

The sex assault included anal penetration using objects such as pens, water bottles, carrots, bananas and pencils.

The incident was the offshoot of a sailor's birthday celebration aboard the warship when the celebrants, both male and female, were sexually assaulted with elongated objects. In one instance, a whiteboard lid came off in a male sailor's anus who ran out screaming because of bleeding, according to a former sailed known as Bridget.

The eight have escaped court martial but would still face administrative action ranging from formal warnings to termination. The administrative action is being pursued because the internal investigation failed to produce enough evidence to file criminal charges against those involved in the sex assault.

The eight sailors were given several weeks to convince the authorities why they shouldn't be punished for their involvement.

Vice Admiral Ray Griggs, chief of Navy, who urged all Navy members to come forward if they have been victimised by such hazing rituals, said, "We have worked to clearly articulate what behaviour is appropriate in our workplace. Accountability is a feature of our cultural change program. All personnel are aware that Navy will not tolerate unacceptable behaviour."