Attacks on guide dogs by other dogs are on the increase according to a new study - with more than 100 a year.
Figures show that between 2010 and 2015 there were more than 629 attacks which is an increase to 11 per month last year from three per month in 2010.
Handlers have reported feeling upset, shaken and anxious after an incident - with 87 people left with injuries, of which 59 were guide dog owners, and 41 needed medical attention.
More than 43% of the animals injured required vet treatment at an estimated annual cost of nearly £35,000.
As a result of the attacks more than 20 dogs were withdrawn from the Guide Dogs programme - 13 of which were fully qualified and working with owners - resulting in a £600,000 cost to the Guide Dogs charity.
Under the Anti-Social Behaviour, Crime and Police Act passed in 2014, a dog attack on a trained assistance dog will be treated as an aggravated offence.
This means prison sentences of up to three years could be handed to the owner of the attacking dog.
The authors of the study say it is not clear if the rise in attacks is because of a real trend or because of an increase in people reporting them.
But they found that more than 54 dogs were attacked more than once during the study - with 46 attacked twice, seven dogs attacked three times and one dog attacked four times.
There are currently more than 4,900 working guide dogs in the UK, providing support and mobility for blind and partially sighted individuals.