FAMILY members of some of the teenagers involved in the alleged attack of a teenage girl posted on social media were so horrified by the situation they either reported them to police or drove them to a police station.

Far North police Det Insp Jason Smith has praised the actions of family and other community members for their response to the graphic recording which he said had "suitably horrified" officers.

Four teens have been charged with the alleged assault of the 15-year-old girl near Bicentennial Rd on Saturday, two facing charges specifically linked to filming the incident.

The girl sustained multiple bruises and received medical treatment.

Among the four charged were three girls aged 16, 15 and 13, and a 13-year-old boy.

The boy and oldest girl were both charged with either making or distributing child exploitation material along with assault offences.

Det Insp Smith said police believed the alleged assault occurred after an altercation between two parties the day before.

He said filming the incident and putting it on social media was allegedly done to "promote the offence" and did not assist police in identifying those involved.