Concerns have been raised over a 17% spike in assaults against Dundee emergency workers.
In total, 110 members of the police, fire, ambulance and other emergency services were attacked between October and December.
The figures revealed in a new police report contrast with the 94 recorded during the same period of 2013.
While the numbers are not broken down service-by-service, David Forbes, regional organiser for Unison, claimed delays in ambulances reaching non-life threatening incidents may explain the rise.
He said: “Clearly one attack is one too many and drink and drugs have a large role in this behaviour. But I think the Scottish Ambulance Service has done all it can do to stop them.
“As long as we are confident the service is keeping members up to date with danger spots then we are content.
“But one concern is the friends of those being treated are also assaulting paramedics. They are lashing out as part of their frustration about waiting so long for treatment.
“If we were looking for an explanation, there has been a rise year-on-year in demand for ambulances and as a result there will be more delays for non-life threatening emergencies.”
While the assaults increased in Dundee, there was actually a drop overall in Scotland for assaults on emergency service personnel during the same period.
The figures across the country fell by 5.4%, from 5,268 to 4,984.
Dundee health and social work convener Ken Lynn said: “Dundee is a city and there will be far more drinking establishments and a higher concentration of revellers than places in the countryside.
“But that’s not an excuse for these incidents happening and one assault is one too many.”
A Scottish Ambulance Service spokesman said: “Ambulance staff are subjected to verbal and physical abuse from the public on an almost daily basis while trying to help people and in the majority of these cases alcohol is a key factor.
“Assaults or threatening behaviour are reported to the police.”