Two Muslim women have claimed they were refused a bus ride because one had her face covered by a veil.
The students, both 22 and from Slough, Berkshire, boarded a Metroline bus from Russell Square to Paddington, London.
But they said when they presented their tickets on Tuesday, the driver told them they were a "threat" to passengers and ordered them off the bus.
The firm has started an "urgent" investigation. The Muslim Council of Britain said it was "deeply concerned".
The pair, who have made a formal complaint to the bus company, have asked the BBC not to reveal their full names.
Yasmin was wearing a hijab and Atoofa was dressed in a niqab - which covers the face.
Yasmin said at first she boarded the bus by mistake when it was not in service to ask where it was going, but was told by the driver to get off.
"About 10 minutes later... the passengers started getting on. When I went forward to show my ticket he said, 'Get off the bus'. I presumed he was still angry because I got on the bus before.
"He said, 'I am not going to take you on the bus because you two are a threat.'
"I realised it wasn't due to me getting on the bus, this may be a racist attack."
She asked for his contact details but when he refused she began to film him and he covered his face.
"I said, 'It's OK for you to cover your face on my recording but it's not OK for my friend to cover her face out of choice?'
"There was no point arguing with him, we got off the bus and by then my anger turned into emotion."
BBC News
