SYDNEY, Australia (AP) — Five teenagers brandishing baseball bats and a machete rampaged through a school in Sydney on Monday, smashing windows, terrorizing students and hitting a teacher over the head, police said. Eighteen students were also slightly hurt.

The five, between the ages of 14 and 16, were arrested after storming into suburban Merrylands High School and would likely be charged with assault and other crimes, Police Detective Inspector Jim Stewart said.

The offenses carry penalties up to seven years in prison.

One teacher was treated at a hospital after being hit on the head with a bat when he tried to stop the attackers, and 18 students were treated for cuts from broken glass and other minor injuries, Stewart said.

"It beggars belief they would attempt this kind of activity against innocent students," Stewart said.

Police were questioning the suspects — who were not identified because they are minors — about their reasons for the attack, including whether they were looking for someone in particular.

"The information to us is they were coming here ... seeking someone," Stewart said.

Police refused to say whether the alleged attackers were students at the school.

The drama unfolded as hundreds of students attended a routine assembly in an outdoor area of the school about 9 a.m. As the attackers moved in, brandishing weapons, teachers rushed the students back to class, where they sought refuge behind locked doors, under desks, even in a cupboard.

Worried parents rushed to the school as students flooded the airwaves with mobile phone calls and news of the attack was broadcast.

Stewart said the attackers defied teachers who tried to stop them, but did not challenge police when they arrived, and surrendered their weapons without a struggle. The raid lasted just six minutes, the Education Department in New South Wales state said.