An acid victim has said he was attacked on his doorstep by two unknown men who apologised for what they were about to do.
Chris Bonney, who was attacked in February 2016, told Victoria Derbyshire the men had said: "Are you Chris? We're ever so sorry," before the attack.
Mr Bonney was left with scars across his face and body, depression, post-traumatic stress disorder and anxiety.
Police had been unable to find a motive or any evidence, he said.
And officers had been able to tell him only that "the people who did it were clearly paid to do this job".
A recent acid attack at a London nightclub left two people each blinded in one eye and several others with severe burns.
Mr Bonney, from Weymouth, Dorset, told the BBC's Victoria Derbyshire programme he had been left in "excruciating pain".
The image below shows some of the injuries he received.
The acid, he said, had "melted the paint off my front door… burnt through radiators, destroyed everything it touched".
Its first impact was to the left side of his face, and then his left arm.
It left him in hospital for three weeks.
He said he would "cry myself to sleep at night" because of a fear of the dark emanating from the attack.
'Needs to be education'
The cause, he said, had been in part the inability to "process what had happened to me", or the reasons why.
He has since received counselling.
Mr Bonney - who works as a college lecturer - has never been caught up in criminal activity.
He said he had "never seen" his two attackers before. "It was completely random."
Mr Bonney said the attack had caused "significant scarring, and made my skin susceptible to infections".
His vision was also impaired as his eyelid was fused to his eyebrow.
Mr Bonney hopes that one day the perpetrators will be caught, but worries how readily available the acid is to buy.
"There needs to be some sort of education," he said, "that it's not acceptable to use it as a weapon".
"We educate how bad knife crime is, but substance attacks are becoming more frequent now."
Figures from police forces across the UK suggest that the number of assaults involving corrosive substances has risen by 30% in two years.
Since 2010 there have been more than 1,800 reports of attacks involving corrosive fluids in London.
Mr Bonney, who has a newborn baby, said he was now "looking forwards - looking at the positives now, not the negatives".
Watch the Victoria Derbyshire programme on weekdays between 09:00 and 11:00 on BBC Two and the BBC News channel.