A woman was threatened with violence on a Sydney bus after she started filming an elderly couple she claims had been taking photos of her on what looked like professional cameras.

In a video posted to Facebook on Wednesday, 21-year-old Alexandra Clay was confronted with some blunt threats of violence for filming an older man and woman she claims were taking photos of her.

"This happened last year but I saw them on the same bus again this morning and they're still f**ked," Ms Clay wrote on the post.

"They take photos of you on professional cameras against your will and refuse to delete them."

View photos The man threatened to knock Alexandra Clay out when she started filming on the bus last year. Source: Facebook More

View photos Ms Clay spotted the couple taking her photo and decided to confront them on video. Source: Facebook More

Ms Clay said she was certain the woman was taking photos of her, even spotting some showing her face at close range.

When Ms Clay took out her phone to film the couple as she confronted them, she was met with threats of violence from the older man.

"What are you some pervert or something? What are you taking photos of me for?" Ms Clay says to the couple.

View photos Ms Clay said the pair had a 'professional camera' with them and was taking photos of her. Source: Facebook More

"I don't f**king know you. Can you delete them please?"

The elderly man in a blue polo shirt steps up to Ms Clay and tells her to put the phone down "or I'll knock you out".

The man can be heard telling Ms Clay he will throw her off the bus, even raising his fist and counting to three.

View photos The man threatened to knock Ms Clay out, raising his fist and counting to three. Source: Facebook More

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