A woman and two children have been arrested after alleged assaults at Armidale Secondary College

A woman and two girls have been arrested after four staff members and police were allegedly assaulted at a high school.

A NSW high school went into lockdown during a violent incident where four staff members were allegedly assaulted by two girls aged 11 and 13.

Police were called to the Armidale Secondary College on Butler St in Armidale, about 480km northwest of Sydney, following reports two students had assaulted staff about 10.30am on Tuesday.

Officers were told the girls aged 11 and 13 had allegedly attempted to assault another student before they set upon staff.

The 13-year old girl allegedly assaulted one of the police officers during their arrest at the school.

No students were injured but four staff members were treated for minor injuries and two were taken to Armidale Hospital for further treatment.

A woman and two girls aged 11 and 13 were arrested after four staff members and police were allegedly assaulted at Armidale Secondary College in NSW. Picture: Supplied

Police allege a 34-year old woman arrived at the school during the incident and verbally abused staff and police.

Officers issued her a move on direction, but claim she refused and was arrested.

The woman was taken to the Armidale Police Station where she was charged with failing to comply with a direction, resisting police and intimidating a police officer.

The woman was refused bail to appear before Inverell Local Court on Tuesday.

A woman aged 34 was also arrested after she allegedly abused police and refused to comply with police during the incident. Picture: NewsWire/ Gaye Gerard

The two girls have been released pending further investigations.

Armidale Secondary College principal Kim Allford said in a letter to parents they enacted their lockdown procedure to allow staff to deal with a “student behaviour matter.”

Students were kept in their classrooms with teachers until the matter had been dealt with at 11.45am.

Mr Allford said students were informed about the incident and were offered support.

The NSW Education Department has been contacted for comment.

Originally published as A woman and two children have been arrested after alleged assaults at Armidale Secondary College