Latest: Residents have been evacuated after a suspected car bomb exploded in Derry.
The PSNI as well as firefighters and the ambulance service sealed off the scene close to a courthouse on Bishop Street in the city.
Police have also indicated on their PSNI Foyle Facebook page that they are concerned about a second car on the street.
Witnesses earlier said they heard a loud bang and saw a large plume of smoke.
Local residents, including those in a sheltered housing complex for elderly people, are being evacuated.
There has been no reports of any casualties at this stage.
A photograph was tweeted from a PSNI Twitter account warning people to stay away from the area.
The tweet from the PSNI’s Derry City and Strabane District account also warns members of the public that Bishop Street is currently closed, adding the words “suspected car bomb”.
A further update was posted on the PSNI’s Foyle Facebook page.
“As far as we know no one injured. There is another car we are not happy about. There are ongoing necessary evacuations.”
Democratic Unionist Party leader Arlene Foster said it was a “pointless act of terror” which “must be condemned in the strongest terms”.
“Only hurts the people of the City. Perpetrated by people with no regard for life,” she said.
“Grateful to our emergency services for their swift actions which helped ensure there have been no fatalities or injuries.
This pointless act of terror must be condemned in the strongest terms. Only hurts the people of the City.
Perpetrated by people with no regard for life.
Grateful to our emergency services for their swift actions which helped ensure there have been no fatalities or injuries. https://t.co/IMJ7Dn9rAa— Arlene Foster (@DUPleader) January 19, 2019
Sinn Fein Foyle MP Elisha McCallion has condemned the explosion.
“This incident has shocked the local community,” she said. “In particular, there are many elderly residents who live in the area who have been alarmed.
“Thankfully no-one appears to have been injured.
Very disturbing news from L~Derry this evening. Hope that no-one is hurt. Police now reporting a second suspicious vehicle in the area.January 19, 2019
“Derry is a city moving forward and no-one wants this type of incident. It is not representative of the city.
“I would encourage anyone with information about this incident to bring it to the police.”
Local Democratic Unionist MLA Gary Middleton condemned the incident as a “disgraceful act of terrorism”.
“PSNI have confirmed there were no injuries in the serious incident at Bishops Street,” he said.
“Vehicle hijacked with explosion outside courthouse. Disgraceful act of terrorism.”
PSNI have confirmed there were no injuries in the serious incident at Bishops Street. Vehicle hijacked with explosion outside courthouse. Disgraceful act of terrorism. pic.twitter.com/X0YoUT7ZUb— Gary Middleton MLA (@Gary_Middleton) January 19, 2019
Alliance Party leader Naomi Long has also voiced her concern about the incident on Twitter, describing it as “very disturbing news”.
The incident happened just a few miles from the border ahead of the 100th anniversary of the war of independence.
The first shots of the war were fired at Soloheadbeg, Co Tipperary on January 21 1919.
Violent dissident republican groups have been responsible for a number of murders over the last 10 years.
They include the killing of Sappers Mark Quincey and Patrick Azimkar outside Massereene Barracks in Co Antrim in 2009 and PSNI Constable Stephen Carroll in Craigavon, Co Armagh in the same year as well as Constable Ronan Kerr in Omagh in 2011.
Dissidents were also responsible for the murders of prison officers David Black in 2012 and Adrian Ismay in 2016.
There have also been a number of narrow misses, including the maiming of Constable Peadar Heffron in 2010, when an undercar booby trap bomb left him seriously injured.- Press Association
A suspected car bomb has exploded in Derry.
A photograph was tweeted from a Police Service of Northern Ireland Twitter account showing what appears to be a vehicle ablaze.
The tweet from the PSNI’s Derry City and Strabane District account also warns members of the public that Bishop Street is currently closed and to stay away, adding “suspected car bomb”.
The incident appears to have taken place close to a courthouse.
Bishop Street Closed
The PSNI said: "Police are in attendance at the scene of an incident in Derry city centre.
"We would ask for patience and co-operation of the public and the business community as we carry out our initial investigations.
"Any info to 101 or Crimestoppers on 0800 555 111."
- Press Association