Police hunt teen over SA lake assaults

Police have released a photo of a youth they believe has information about incidents in which a teenager has been indecently assaulting women as they walk around an Adelaide lake.

The youth, likely aged 16 to 18, has been grabbing or patting women on the buttocks as he rides past on a BMX bike, police say.

He's believed to be responsible for at least 12 incidents in the Mawson Lakes area since October.

The most recent incident happened on Tuesday afternoon.

The offender is described as Caucasian in appearance, with a thin build and long shoulder-length blond hair.

Senior Constable Chris Webber says police are taking the incidents seriously.

"We're putting high visibility police around the area, either to deter him or to detect him if it happens again," he told reporters on Thursday.

The youth's actions were unlikely to escalate but would not be tolerated, Snr Const Webber said.

"While this person may think that grabbing a woman's buttocks is a joke or trivial matter, it is actually a serious charge," he said.