Updated 6.44pm

Three people trapped deep inside a Spanish potash mine when a gallery collapsed earlier on Thursday have died, Catalan leader Pere Aragones said.

"Unfortunately, we can confirm the death of three young people who were working in the mine," he told reporters outside Cabanasses mine in Suria, 75 kilometres (46 miles) northwest of Barcelona.

Rescuers had recovered and identified the bodies of three people who were "around 30 years old", Aragones said, sending his deepest condolences to their families and colleagues.

Rescuers said the trio had been trapped "at a depth of about 900 metres" (2,950 feet) after one of the galleries collapsed just before 9:00 am (0800 GMT). 

Despite frantic efforts to reach them, it was hours before rescuers got down to the place where they were and were able to confirm their deaths.

"The information we have makes us fear the worst," regional interior minister Joan Ignasi Elena had told reporters at the mine a few hours before as the rescue efforts continued. 

An emergency vehicle arrives at the potassium mine where three people were trapped after a collapse, in Suria.

The rescue was complicated by the need to ensure the safety of the teams involved, he said, indicating it would be "reckless" to rush such an operation. 

Just after midday, Aragones had announced their deaths on Twitter saying: "We deeply regret the death of the three miners in the accident in Suria mine."

Several minutes later, he deleted the tweet. 

Many local and national media outlets also said they had died, citing sources in the emergency services, but police said they could not confirm the reports until "they were reached by a doctor" and their families had been notified.

- 'No warning' -

When the gallery collapsed, all three were carrying out "a routine task that they do every day", mine worker Carlos Arnaldo told reporters at the scene. 

He said it was "difficult" for him to believe that they might have survived. 

"Sometimes the mine gives you no warning: the roof caves in and nothing can be done," he said. 

"This is terrible news," tweeted Labour Minister Yolanda Diaz, sending "love and solidarity to the families and colleagues of the workers caught up in the collapse at the Suria mine". 

Owned by ICL Iberia, the Spanish arm of Israel's ICL Group, which specialises in fertilisers and chemicals, the Cabanasses mine had recently passed a security inspection, officials said.

A fire helicopter flies over the potassium mine where three people were trapped after a collapse. The fate of the three miners trapped remained unclear after a tweet by regional leader confirming their deaths was then deleted.

"The last inspection was just three weeks ago and it was cleared without any sign of irregularities," Catalan regional business minister Roger Torrent told reporters at the scene. 

ICL Iberia is the only company that produces potassium salts in Spain, handling both the extraction, treatment and marketing, its website says. 

Based in Suria, it has 1,100 employees.

Two miners died in December 2013 when a gallery collapsed at the same mine, the Catalan press reported at the time, citing an official statement.

The last major mining accident in Spain was two months earlier, in October 2013, when six people were killed and five others injured following a gas leak at a coal mine in the northwest. 

It was the worst accident at a Spanish mine since 14 miners were killed in August 1995 during a methane explosion at a coal mine in the northern province of Asturias.