The driver of a gritting lorry has been injured after the window of his vehicle was smashed in Ballykelly.
Youths throwing snowballs and stones attacked the gritter as it travelled along Drummond Park in the village on Thursday night.
The driver sustained a cut to his cheek.
A spokesperson from Roads Service appealed for an end to attacks "as we try to provide this vital service".
DUP councillor George Robinson said he "unreservedly condemned" those responsible.
"I'm appalled that anyone could stoop to such lows, particularly at this time when those drivers are out doing an essential job for the community.
"I hope the culprits are caught and brought before a judge and given the heaviest sentence possible."
SDLP MLA John Dallat said it was "despicable"
"Those responsible should be utterly ashamed of themselves.
"I urge parents who have children off school to be aware of their actions and make sure they act in a responsible manner at all times in the poor weather."
Last month gritting was temporarily suspended in parts of Londonderry after youths attacked gritting lorries.