No-one was injured in the attack, which has been condemned as “unbelievably reckless.”
Secretary of State Karen Bradley says those responsible would not be permitted to disrupt progress in Northern Ireland.
“The small number of people responsible have absolutely nothing to offer Northern Ireland’s future and will not prevail,” she said.
“Our voices across the political spectrum are united. This is intolerable violence and we want to look forward and build a peaceful future for all in Northern Ireland.”
Mayor of Derry John Boyle said: “I would actually like to ask the people responsible for this what it actually was that they thought they were going to achieve. It achieves nothing, it didn’t achieve anything in the past, it didn’t achieve anything right now.”
The Irish nationalist New IRA is one of a small number of militant groups opposed to a 1998 peace deal that largely ended three decades of violence in the British-run province. They have carried out sporadic attacks in recent years.