Justin Bieber delighted elementary school children in Los Angeles on Thursday by staging a surprise mini-concert outdoors.

The Baby hitmaker treated some pupils and teachers at MacArthur Park Visual and Performing Arts Elementary to renditions of songs including Intentions and Holy during the special welcome back event, hosted by officials at the Baby2Baby children's charity and online retail giant Amazon.

New mum Kelly Rowland, a board member and ambassador of Baby2Baby, was also in attendance to hand out school supplies and toys to youngsters.

Taking to Instagram to reflect on the celebration, the R&B star wrote, "I was so proud to join @Baby2Baby and @Amazon to welcome students back to school after a year of learning remotely.

"Thank you Amazon for helping us provide backpacks filled with hygiene items, face masks, hand sanitizer and school supplies as well as food, diapers, clothing and more to ensure that children and their families have the essentials they need to stay safe while at school and at home.

"Follow @Baby2Baby to keep up with their amazing COVID-19 relief work!"

Bieber's wife, model Hailey Bieber, was among the lucky group to watch the singer's show, which was held two days after California Governor Gavin Newsom announced all students from kindergarten to 12th grade are expected to return to in-person classes this autumn.