Disguised teens intimidate school: police

Two teenagers covered head-to-toe in black costumes have allegedly taunted students during a school pick-up in Sydney.

The strange sight of the duo in body-length suits with their faces completely covered took a threatening tone when the pair allegedly made "cutting" gestures towards students, police say.

Police have been told the two people made the intimidating gestures outside the Dulwich Hill school in Sydney's inner-west on Wednesday afternoon.

When officers arrived the pair were nowhere to be seen.

Police allege the black-clad duo were seen outside the school again by students and parents during the busy school pick-up period on Thursday.

Marrickville police Inspector Alfio Sergi said the students felt intimidated.

"It shook them and the parents because they are young kids," he told AAP.

A 14-year-old boy and a 18-year-old were arrested by police.

They were charged with an intimidation-related offence and granted bail to appear in court in October.