Police have said that one of their vehicles was struck by gunfire in the city in the early hours of Tuesday.
The vehicle was being driven along Westland Street, close to the Bogside Inn, shortly before 1am when it was struck twice. There were no injuries to officers in the vehicle.
The type of gunfire has not yet been established. A line of enquiry is that dissident republicans planned and carried out the attack.
The nature of the damage to a window of the Land-Rover was established only after a detailed ballistic examination.
Police have described the incident as totally reckless.
Superintendent Garry Eaton, the G District Operations Manager, said: “It is fortunate that we are not speaking about deaths or injuries today. Members of the crew were kept safe by protective equipment on the vehicle, however if the shots had missed, then anyone walking or standing on the street could have been hit.
“The officers were carrying out normal patrolling to keep the community safe. Those who organised and carried out the attack were totally reckless and showed total disregard for the lives of people in that community.
“Despite this incident; we remain committed to providing the people of Derry with the type of positive and dedicated policing that they ask and expect of us.”
Detectives are appealing for information. Information can be given on the police non-emergency number 101. Alternatively, it can be provided to the Crimestoppers charity anonymously on 0800 555 111.