A man who was filmed repeatedly throwing his three-year-old stepdaughter in a swimming pool, causing her to drown, has been jailed for 100 years.

Horrifying surveillance footage showed the killer, identified only as Jose David N., throwing the child into the water at a hotel in the city of Morelia, in the south-western Mexican state of Michoacan in August 2015.

She is seen battling to keep herself afloat, while the murderer stands at the side of the pool doing nothing.

The helpless little girl could not swim, and other bathers did nothing to try and save her.

A man, identified only as Jose David N., has been jailed for 100 years after repeatedly throwing his stepdaughter into a swimming pool, causing her to drown

The youngster's mother, who is a nurse, did not realize her child was dead until after she had made one more visit to the pool with her husband.

They then returned to find the lifeless girl in front of the TV, prompting them to take her to hospital.

She died a short time later. The mother claimed she did not know her daughter was being mistreated until she saw the shocking video clips.

The incident took place on 12 August 2015 while the little girl's mother was sleeping in their hotel room.

It caused outrage in South America after the footage was made public last year.

The horrific CCTV footage showed the killer continuously dump his stepdaughter in the water and watch as she struggled

Jose knew his stepdaughter could not swim but pleaded surprise after being told that she had drowned, the court heard.

However, the video footage proved enough to convict him and see him jailed with no possibility of parole.

Jose stayed silent throughout his murder trial and did not testify. Prosecutors had recommended a prison sentence of up to 40 years.

But a judge made his punishment more severe after reviewing the footage.

It shows him standing at the poolside as her arms flail in the air.

She reaches out for help, before throwing in a lifebuoy, but the little girl is too weak to grab it.

The little girl was unable to escape the inhumane treatment and onlookers reportedly declined to step in and stop it

At one point he throws her in and walks away before returning and tossing her back in when she is fully-clothed.

After deliberation, judges Juan Salvador Alonso Mejia, Ana Lilia Garcia Cardona and Noe Reyes Millan found him guilty of aggravated murder.

The judge, Garcia Cardona, who read the sentence, said that not only did the man throw the toddler into the pool several times, he even dragged her by the hair under the water.

He then held her tiny body in such a position that she was unable to breathe.

The defence had tried to suggest that the little girl had died outside the pool and not in the water, but this was rejected by the judges.

The mother is said to have taken her daughter to hospital after realising she wasn't breathing and doctors confirmed she had died.

The stepfather was arrested and detained a short time later.

At one point in the disturbing video, he is seen holding her under the water