Image caption Vern Unsworth (R) helped bring top international cave rescuers to the mission, including Rob Harper (L)

A British cave diver who helped rescue 12 Thai boys from deep within a cave has said he is considering suing tech entrepreneur Elon Musk.

In now-deleted tweets, Mr Musk had called Vern Unsworth a "pedo guy" after the cave expert ridiculed a mini-submarine built by Mr Musk for the rescue effort as a "PR stunt".

Mr Unsworth told reporters on Monday that he was considering legal action.

"It's not finished," he told Australian network Channel 7.

Thailand-based Mr Unsworth's knowledge of the cave complex is said to have played a key role in the rescue effort. He travelled into the caves in the first days after the boys went missing and helped bring in top international cave rescue experts for the mission.

Mr Unsworth had earlier said the mini-sub built by Mr Musk's team, and flown to Thailand before being rejected as inappropriate for the rescue mission by Thai officials, would have had "absolutely no chance of working".

Elon Musk, who regularly takes on journalists and other critics on Twitter, on Sunday tweeted a response to Mr Unsworth, without using his name but calling him a "British expat guy who lives in Thailand".

He said he would make a video showing the mini-sub making it deep inside the cave "no problemo", adding: "Sorry pedo guy, you really did ask for it".

Image copyright Twitter

Mr Musk did not back down when challenged.

Image copyright Twitter

He later deleted the tweets - which were sent to his more than 22 million followers - and is yet to publicly respond to the outcry.

"Yes," Mr Unsworth said when asked if he would consider legal action.

The BBC has contacted Mr Musk, via his company Tesla, for comment.

All 12 boys and their young coach were rescued last week from the Tham Luang cave system after a complex and treacherous rescue operation involving hundreds of volunteers. They had become trapped in the cave by rising floodwaters on 23 June and were first found by rescuers on 2 July.

The 13 rescued remain in hospital in the city of Chiang Rai but are expected to be discharged on Thursday.

Last week, as the rescue effort was under way, Mr Musk hit out at the Thai official in charge of the mission's command centre, Narongsak Osotthanakorn, after he said the mini-sub was "not practical with our mission", though it was "technologically sophisticated".

Mr Musk responded by saying Mr Osotthanakorn had been "described inaccurately as 'rescue chief'" and was "not the subject matter expert".

He also tweeted an earlier email from Richard Stanton - one of two British caving experts called in to front the rescue - who had urged the business leader to build the capsule as quickly as possible.

Mr Unsworth told the AFP news agency that he would make a decision on whether he takes legal action against Mr Musk after flying back to the UK this week.

"He's just a PR stunt merchant - that's all he is," he said.