Two New York City schoolboys, ages 9 and 12, were arrested Wednesday for putting poison into their teacher’s water bottle, police told the Associated Press

The incident occurred on Monday at P.S. 315 in Brooklyn. The students, who are being treated as juveniles, were charged with criminal possession of a weapon, reckless endangerment and attempted assault, ABC reports.  

Deputy Police Commissioner Stephen Davis said Wednesday that the younger of the two boys brought the poison to school and he is also the one who physically put it into the water bottle. The older boy just assisted. He said the boys wanted to see what would happen to the teacher.

Sgt. John Buthorn of the New York City Police Department told CNN that the woman, a teacher at P.S. 315, was treated by her doctor and is in good condition. 

The type of poison has not been confirmed, but preliminary tests point to rat poison, in pellet form. When ingested by humans, rat poison can have a number of effects that include liver failure, convulsions, difficulty breathing and hemorrhage. According to police, the teacher immediately brought the water bottle to the school's principal after drinking from it and felt nauseated the day after the incident.

“We are greatly relieved that the teacher is recovering and we continue to closely monitor this situation,” the city department of education said in a statement. “Ensuring the safety of our entire schools community is our priority, and while this matter is still under investigation, we will take swift and appropriate action.”