Image copyright Reuters

Taylor Swift's ex-bodyguard has backed her sex assault claims by testifying that he saw a radio DJ reach under her skirt at a 2013 concert.

Greg Dent told a Colorado court he "did not see his hand touch her physically", but "saw his hand under her skirt".

Swift, 27, is suing ex-radio DJ David Mueller, 55, for allegedly groping her after she agreed to pose for a photo with him and his girlfriend.

Mr Mueller sued the star for $3m (£2.3m), claiming she cost him his job.

Ms Swift countersued a month later for the symbolic amount of $1, and has described the groping incident as "completely intentional".

The alleged assault is said to have occurred in 2013 during a Denver stopover on the singer's Red tour.

Mr Mueller, then a host on the top-rated radio station KYGO, had been invited to meet her before the show.

Ms Swift complained to KYGO and the station fired Mr Mueller two days later.

On Friday, Ms Swift's lawyers asked the judge to throw out the case against the pop star, arguing that she did not instruct the radio station to fire Mr Mueller.

Mr Dent, who no longer works for Swift, told the court on Friday in Denver, Colorado, he was steps away when Mr Mueller posed with his girlfriend and the pop star.

"She reacted, pushed her skirt down and moved over closer to [Mr Mueller's girlfriend]. So in my opinion, I knew he touched her," he said.

Mr Dent explained he did not act because "he didn't sense danger after he touched her", and Ms Swift did not signal that he should intervene.

The Shake It Off and I Knew You Were Trouble singer, however, later complained and Mr Dent confronted Mr Mueller at the event.

His testimony came a day after Ms Swift took the stand to describe the incident, calling it a "definite grab. A very long grab."

When Mr Mueller's lawyer, Gabriel McFarland, asked why her bodyguard did not interfere when the alleged incident happened, the pop star said: "No-one could have expected this to happen.

"It had never happened before. It was horrifying and shocking."

Image copyright Reuters / Jeff Kandyba Image caption Taylor Swift (left) has been present throughout the trial, often accompanied by her mother Andrea (second right)

Mr Mueller's ex-girlfriend who was also in the photo, Shannon Melcher, also testified on Friday.

She said she noticed nothing amiss during the brief meeting and that she and Mr Mueller were rudely escorted out of the arena later that evening.

Ms Melcher added that Mr Mueller was devastated by the allegations.

Mr Mueller's former radio show co-host, Ryan Kliesch, testified that he did not know his former colleague to be disrespectful toward women.

He added when he heard the allegations, he "thought it was a joke".