Four juveniles were arrested Thursday after a brawl outside of Main Street Elementary School that was allegedly sparked by a threat on MySpace, according to police.A student at Cardinal O’Hara High School was allegedly threatening a Main Street student on the social networking site, according to Police Chief John Easton.

The sister of the girl allegedly being threatened and another girl were dropped off at Main Street Elementary as school was letting out, Easton said.The girl allegedly making the threats was there to pick up her siblings, according to Easton. The subsequent encounter escalated to a brawl, Easton said.

When the chief and Officer Brian Boyd tried to break up the fight, the two sisters allegedly resisted, punching and kicking police.A teacher saw what was happening and tackled the O’Hara girl, police said. All three were taken into custody.

The fourth girl, a student at Toby Farms Elementary School, was not involved in the fight, but was arrested when she refused orders to leave and shouted obscenities at the principalThe girls, who were not named because they are juveniles, were released to the custody of their parents.

Easton said he has the license plate number of the adults who dropped the two girls off at the school. He is considering charges against those adults.