Investigators are trying to determine who is responsible for making death threats on social media against a middle school student in San Dimas, authorities said.
The series of threats and denigrating messages recently posted on
Some of the posts show various photos of the victim with captions such as, "Your life is very short sweetheart, this is you last week! Times up!" and "That smile! I cant wait till its just blood and tears."
Sheriff's deputies increased their presence in and around the school campus and around the victim's home last week, authorities said.
"Our primary concern is the safety of the students," the sheriff's department said in a prepared statement. "We will continue to focus our efforts on preventing violence and any further threats."
The threats were reported by various sources, including some students who told school administrators, one official told the San Bernardino Sun.
Instagram, which is owned by Facebook, is cooperating with authorities in the investigation.
"We are encouraged by the findings of the investigators so far," sheriff's officials said in a prepared statement. "The forensic process of gathering electronic evidence often takes several rounds of search warrants, as we follow up on information we receive. The investigation seems to have a good likelihood of a definitive answer in the end."
But authorities warned parents to be aware of their children's activities online.
"Conflicts at school, and bullying, are very real problems," the sheriff's department said in its statement. "Children are sometimes suspended or expelled from school based on the serious nature of threats, often considered crimes, or at least violations of school policies."