A peaceful playground in Puerto Rico turned into a park of terror Thursday after a 14-year-old girl went on a needle-wielding rampage Thursday – stabbing 37 kids and sending school officials and parents into crisis mode.

"She would stab one, run, stab another, run, like it was some sort of joke," Education Secretary Jesús Rivera Sánchez said about Tuesday's lunchtime attack on 12- to 14-year-olds at the José de Choudens middle school in the southern coastal town of Arroyo.

Health Department spokeswoman Margarita Casalduc said it was unclear if the syringe contained anything and further tests were needed to determine if it was contaminated. But the victims, accompanied by their shaken parents, gathered at a convention center to be tested for HIV and hepatitis C and to be given preventive medications.

Sánchez said counselors also were helping the victims and their parents.

Social workers were interviewing the alleged attacker to try to determine a motive, Justice Department spokesman Fidel Rodríguez said. He said no charges had yet been filed, but officials said she had been suspended from school.

Rivera said the girl first told investigators she found the syringe, but later said she stole an unused one while visiting a relative at a hospital and had planned to pierce her ear with it. He said it was not clear why she decided to attack her classmates.

A woman who answered the phone at the school said the director, Gloria Ramos, was not available for comment.

Based on reporting by The Associated Press.

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