HUNDREDS of concertgoers have been left injured after a pier collapsed into the sea during a Spanish pop festival.

Two children were among the 313 people left with broken arms, legs and other injuries in the freak accident during the O Marisquiño festival in the city of Vigo, The Sun reported.

Five people are believed to be in a serious condition, but there were no fatalities as a result of the incident.

Spanish newspaper Faro de Vigo said the wooden pier collapsed during the first song of the concert, just after the singer Rels B told the crowd to jump.

There were scenes of panic as revellers plummeted into the sea and were unable to get out just after midnight.

Aitana Alonso, who attended the festival, told local paper Diario de Vigo: “The floor gave way beneath us as if we were in a lift. It was a question of five seconds.

“The platform broke and we all fell. People landed on top of me. I tried to get out and couldn’t. My foot ended up stuck in the water but I managed to free it before a boy gave me his hand and pulled me out.

“There were people underneath me, shouting they couldn’t get out. I didn’t think I would.”

A friend described the scene as “horrible, chaos, panic”, adding: “I saw a family and the little girl was saying to her dad, ‘If we die here, I love you’.”

“It was the worst moment of my life,” said one of the concertgoers who reported seeing people screaming and running around.

Another 16-year-old said: “We were on the walkway when it opened up. I fell on people and people fell on me. I was hit on the head and then some sort of container fell as well. I tried to get out and someone helped me.”

Police and paramedics rushed to help those injured with ambulances whisking revellers to nearby hospitals.

The head of the Galician region’s health authority, Jesus Vazquez Almuina, told Antena 3 television that 313 people required treatment.

Organisers set up an information point for worried relatives who couldn’t initially find their loved ones.

In a tweet, rap artist Rels B wished “strength” to the injured and advised anyone worried about friends or relatives to contact an emergency information point set up by festival organisers.

City mayor Abel Caballero has announced an investigation will be launched to determine why the wooden platform collapsed.

Vigo’s Port Authority president Enrique Lopez Veiga said he thought it was due to “excess weight”.

The nationalities of those hurt has not yet been revealed.

O Marisquino bills itself as an urban, culture and action sports festival. The drama happened at the start of the last day of the three-day festival, which is in its 18th year.

Visitors number around 160,000 and come to see events including BMX, skateboarding and breakdancing.

An article published in the local press before the start of this year’s festival featured interviews with visitors from all over the world, including Portugal, Venezuela, the United States and Germany.