Yeah I found that surprising as well. Imagine how the people felt who were waiting to get picked up, not knowing if or when a river of lava would be heading there way, or boulders falling out of the sky.

Some questions are being raised now as to why the island, which is privately owned, was allowed to operate as a tourist destination, given it was known to be highly active There had been a raised level of warning in November following increased earthquake activity, but seems like it was still not high alert. Apparently it is a 'steam' volcano, which is harder to predict than a normal one, but still...

Yes, it would have been terrifying on the island. Apart from the above, i understand it released a poisonous gas.