A 16-year-old schoolgirl has been arrested on suspicion of attempted murder after a welfare officer was stabbed at a secondary school.
Meanwhile, a 16-year-old girl has been taken into custody, where she is being interrogated by officers.
The school's head, Gareth Morris, has sought to reassure parents and the community after what he described as an "isolated incident".
The 61-year-old support worker was taken to hospital but her injuries are not life-threatening, officers have said.
A spokesman for the force said the woman is being treated in hospital for "serious but not life threatening injuries".
Ms Wilson said the school had no history of violent incidents and it remained open.
'Staff at the school and police officers responded to this isolated incident very quickly, and one person is now in custody as a result.
"We will support our staff directly affected and will be keeping parents updated throughout the day".
According to Humberside Police, pupils at the school were not "directly affected" by the incident.
'It happened in an office in the school, so all of the rest of the children were completely safe, ' she said.
Winterton Community Academy is a mixed-sex school with 518 students on its rolls.
And in Bradford, Vincent Uzomah was stabbed in the stomach by a 14-year-old boy in a racially motivated attack in front of pupils at Dixons Kings Academy in 2015.
The incident is likely to raise questions about teacher safety in schools, following similar cases in recent years, like that of Ann Maguire.
It adds that the academy has "made an incredible leap forward over the past couple of years", citing an Ofsted report which progressed from a rating of "special measures" to "good with outstanding features".