MELBOURNE, Australia — A bag marked with a swastika and containing a pig’s head was left at the front gate of an Islamic school in Brisbane, Australia, this week.

The police were called to the school, the Islamic College of Brisbane, on Wednesday after the bag was discovered by a groundskeeper and a teacher. The school is one of only two Islamic schools in the state of Queensland.

Ray Barrett, the school’s principal, said that a security camera recorded the episode. Two youths dropped the bag out the window of a blue car at 11:23 p.m. on Tuesday, he said.

Pigs’ heads are commonly used in hate crimes. Most Muslims do not eat pork because the Quran forbids it. Last year, vandals defaced a mosque with graffiti in the state of South Australia, using swastikas and neo-Nazi phrases.