Roadworkers in Rotorua have been shot at with a BB gun, verbally abused and left traumatised in Rotorua, Waka Kotahi claims.

Police have since issued a formal warning to one person after the incident, which took place at a detour point near the Utuhina Stream Bridge.

Waka Kotahi's David Speirs says the bridge repairs have caused a spike in traffic delays during peak times, but there's no excuse for abuse and threats.

"There was quite a high level of trauma as a consequence for the workers involved, but fortunately no-one was physically hurt." 

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