A 12-year-old schoolgirl says she was sexually assaulted after a group of six men in their early 20s approached her on the top deck of a bus.

The girl was travelling to Birmingham city centre with three friends. She told her mother the men approached the group as the bus was in Finchley Road, Kingstanding.

She said her friends had been assaulted and ran down the stairs leaving her alone with the men who then sexually assaulted her.

The four girls were on the top deck of the No.33 bus - which runs from Pheasey to Birmingham - on Saturday, March 16

'No words can describe how I felt when she phoned me,' said the victim's mum, who has issued a plea for information.

'I felt useless as I wasn't there when she needed me the most.

'Police officers are yet to come out to see us. We've only spoken to them over the phone.

'She was really shaken up; there were about six of them.

'The top of the bus was empty, but they went and approached my daughter and her mates.

Travelling to Birmingham city centre (pictured) with three friends the schoolgirl told her mother the men approached the group as the bus was in Finchley Road, Kingstanding

'My daughter's friends were assaulted and they ran downstairs and off the bus. My daughter was left upstairs with them.'

According to the victim's mum, the gang eventually left the bus in the city centre.

The girls were on the top deck of the No.33 bus - which runs from Pheasey to Birmingham - on Saturday, March 16.

West Midlands Police said: 'Police are investigating reports a 12-year-old girl was sexually assaulted on a bus in Finchley Road, Kingstanding, just before 3pm on 16 March.'

Enquiries are ongoing and anyone with information is asked to contact West Midlands Police.