A video appearing to show the sister of a Syrian refugee being attacked at the same school where her brother was allegedly assaulted has emerged.
Footage circulated online shows the boy, 15, being pushed to the ground at Almondbury Community School in Huddersfield, West Yorkshire.
A 16-year-old is to be charged with assault.
A further video of a separate incident allegedly shows the boy's sister being attacked by other pupils.
The footage shows the girl being shoved from behind, and then being pushed towards a grass verge.
At the end of the clip, she can be seen falling to the ground.
In a statement, the West Yorkshire Police said: "We have been made aware of a video showing a girl being assaulted at Almondbury Community School.
"The incident had not previously been reported to the police but we are now liaising with the girl's family who were continuing to support."
The first video, showing the boy being dragged to the ground before the water was poured into his face, was filmed during a lunch break on October 25, West Yorkshire Police said.
His father, who can not be named for legal reasons, told the BBC the attack had left his son "very tired psychologically."
"Because of what happened in the video, my son is shattered," he said.
"He does not concentrate on his studies. When he is asleep he wakes up saying they want to beat me up."
In an interview with ITV News, the boy said he was left feeling like I could not study or do my homework.
In a letter sent to parents, headteacher Trevor Bowen said: "The safety and welfare of students is our number one priority and I can assure you that this situation is being taken extremely seriously."
An online fundraising page set up to help the 15-year-old boy and his family have so far raised more than £ 100,000.