The Met Police in London have stood down an operation in the Oxford Circus area, after they had earlier received reports of gunfire.
No causalities, evidence of any shots fired or any suspects were found in the Oxford Circus and Oxford Street area.
Officers had initially responded "as if the incident was terrorism" after receiving "numerous 999 calls" at around 4.38pm.
Oxford Circus station was closed along with nearby Bond Street station, but they have since reopened.
Oxford Circus and Bond Street stations now both reopened and all trains are stopping normally.
— TfL Travel Alerts (@TfLTravelAlerts) November 24, 2017
In a statement, Met Police said: "Given the nature of the information received, the Met responded in line with our existing operation as if the incident was terrorism, including the deployment of armed officers.
"Officers working with colleagues from British Transport Police carried out an urgent search of the area. No causalities, evidence of any shots fired or any suspects were located by police."
Some cordons remain in place in the area with additional officers deployed, but people who had taken shelter in buildings have now been told they can leave.
British Transport Police reported that one woman sustained a minor injury while leaving the underground station.
At this stage, we have received one report of a woman sustaining a minor injury when leaving Oxford Circus station. There are no other reported casualties. More updates to follow.
— BTP (@BTP) November 24, 2017
Officials say they are working to establish exactly what happened.