The mother of a toddler fathered by Beyonce's music mogul dad Mathew Knowles has filed legal papers demanding an increase in child support payments.

Alexsandra Wright alleged in 2009 that Knowles is the father of her son Nixon, who was born in February, 2010.

A Dna test confirmed Wright's claim and Knowles was subsequently ordered to pay his former mistress $12,000 (£7,500)-a-month in child support.

Wright, who alleged Nixon was conceived during an 18-month fling with the music manager, has now asked a judge to increase the payments to cover security expenses, according to Tmz.com.

She claims she needs the money because Knowles sent her a "threatening" email in 2011. He reportedly wrote, "You hurt my family. There's a price to pay."