Officials have denied editing Texas police dash cam footage showing the arrest of Sandra Bland who died three days later in custody.

Footage of the July 10 arrest shows 28-year-old Sandra Bland’s car being pulled over for failing to signal and then an ensuing confrontation with the officer.

There are several jumps during the 52-minute film, which has had more than one million views on YouTube.

However, Texas authorities say it was not edited and that it will be re-uploaded.

The coroner said Sandra Bland hanged herself in her cell but her family has demanded an independent post-mortem examination.

State officials and the FBI are both investigating her death.

In the video, released by the Texas Department of Public Safety (DPS), Brian Encinia, a white police officer, is seen issuing a ticket and then asking her to stub out her cigarette, which she refuses.

When Sandra Bland refuses to step out of the car, Officer Brian Encinia tries unsuccessfully to pull her out.

He then appears to threaten her with a Taser and says the words: “I will light you up.”

Sandra Bland gets out of the car and they move out of vision, but the audio suggests the confrontation becomes physical before more officers arrive.

Several breaks in the video were highlighted on social media shortly after the film was released with many using the broken footage to question the entire film’s authenticity:

• 25:01 – A man walks away from a pick-up truck and out of shot, before reappearing at the door of the vehicle a few seconds later
• 32:37 – A white car comes into shot then disappears before reappearing a couple of seconds later. The audio doesn’t appear to break during this time, with the officer heard discussing the incident
• 33:04 – The same footage of the white car is looped, again with no noticeable break in the audio

In a statement released on July 22, DPS spokesman Tom Vinger said the video “has not been edited”.

“Some of the video… was affected in the upload and is being addressed. We are working to repost the dash cam video,” he added.

Officer Brian Encinia, who has been on the force for just over a year, said he was kicked during the arrest. He has been put on administrative leave.

Texas DPS director Steven McCraw said his officers have “an obligation to exhibit professionalism and be courteous” but that “wasn’t the case in this situation”.

Authorities also released surveillance video from the jail showing officers responding to Sandra Bland’s death but it does not show the cell.

Jail Sheriff Glen Smith said his staff checked on Sandra Bland less than an hour before she was found dead.

In March, Sandra Bland said she was suffering from “a little bit of depression” and post-traumatic stress disorder in a video posted on her Facebook page.

However, family and friends say Sandra Bland was in good spirits in recent months and had just started a new job. She was also said to be in good health when she arrived at the jail.