The families of five men killed when a wall collapsed at a scrap metal plant in Birmingham have condemned an inquest ruling of accidental death, saying the company’s management should face criminal prosecution.

Almamo Jammeh, 45, Ousmane Diaby, 39, Bangally Dukureh, 55, Saibo Sillah, 42, and Muhamadou Jagana, 49, were killed in July 2016 when a 15ft (4.6-metre) wall made of interlocking concrete blocks collapsed as they were clearing out a storage bay at the Hawkeswood Metal Recycling site.

An inquest at Birmingham coroner’s court heard the men had to be identified by their fingerprints after receiving “devastating blunt-force injuries” when the wall and 263 tonnes of metal ingots in an adjacent bay fell on to them.

The coroner, Emma Brown, had instructed the jury they must return a verdict of accidental death, but said they could decide whether there was a “foreseeable risk” of the wall overturning.

The jury concluded there was a foreseeable risk that the wall would overturn “due to gross overloading” and that the failure to identify that risk had contributed to the deaths.

Court staff handed a box of tissues around the public gallery as relatives of the five men broke down in tears while the jury’s conclusions were read out. Proceedings were paused when one woman’s cries became too loud and she was helped out of the courtroom.

Surrounded by the men’s families, Lang Dampha, a friend of Almamo Jammeh, read a statement outside court. “We are extremely disappointed with today’s verdict and firmly believe our loved ones were unlawfully killed,” he said. “We believe that anyone who sat and heard the evidence at the inquest hearing would agree with us.”

He said it was clear that their loved ones had “died a very violent death” and that the deaths were avoidable. “No one expects to go to work to die … It is shocking for us to think that this could happen in the UK, one of the most developed countries in the world. We never imagined this would happen but we now know why it did.

“We believe it was because of obvious and serious failings by the company that ran the workplace. We believe they didn’t really care about our loved ones. We believe that they thought of our loved ones as cheap labour and didn’t really care if they lived or died.

“In our view the company and its directors should face the full force of the legal system and not be allowed to get away with what has happened. They should face criminal prosecution. Anything less than that will not give us justice.”

The men, four of whom were originally from the Gambia and one from Senegal, had travelled to the UK from Spain in search of a better life after finding it hard to get work following the economic crash in 2008. They were employed through an agency to work as recycling operatives on zero-hours contracts.

In a report referred to in court, the health and safety expert Martyn Ostcliffe concluded that the wall collapsed because it was not properly designed. “It would have been reasonably practicable for the employer to have appointed consulting engineers to design the retaining walls to resist all foreseeable loads,” he wrote.

He added: “The poor and unsafe condition of some of the leaning and defective retaining walls, at the locations around the site, were so severe, the defects would even have been obvious to an untrained layperson.”

Following the inquest, the men’s family members criticised the decision by Shredmet’s directors, Graham Woodhouse and Wayne Hawkeswood, not to give evidence in person to the inquest. In a statement read to the jury, Woodhouse, who was operations manager at the site, said he remained “completely stunned and perplexed that the bay wall collapsed”.

Woodhouse and Hawkeswood, the company’s managing director, said in their statements that they employed a health and safety adviser, Michael White, to carry out monthly inspections of the site and that he had not raised any concerns about the walls.

White was brought in to work for the company in 2010 after a worker’s arm was broken when it became trapped in a piece of machinery, for which the company was fined £50,000.

In his statement to the inquest, White denied he had visited the site every month, saying he had visited only three times in the 12 months before the accident. “I was never consulted by either Mr Hawkeswood or Mr Woodhouse on the erection or dismantling of any wall, nor was I asked to provide a risk assessment for such,” he said.

West Midlands police handed primary responsibility for the investigation into the incident over to the Health and Safety Executive in December. The body has the power to bring criminal charges under the Health and Safety at Work Act 1974, which carries a maximum prison term of two years.

According to figures from the Health and Safety Executive, the waste industry remains one of the most dangerous in the UK, with death rates 16 times higher in 2017-18 than the average across all industries. There were 12 deaths in the waste sector in 2017-18, 10.26 deaths per 100,000. By comparison, there were 38 deaths in the construction sector in the same year, which equated to 1.64 deaths per 100,000.

A statement from the company Shredmet, which runs the recycling plant, said they remained shocked and saddened by the deaths of the men, who they described as “valued work colleagues”. They said they had assisted the coroner in her investigation and continued to assist the HSE in theirs. “We are required to respect the integrity of the HSE investigation and we are therefore unable to comment on it further at this stage,” they added.