Human rights activist and former presidential candidate, Omoyele Sowore, was reportedly taken to hospital after collapsing during a Democracy Day protest in Abuja on Thursday.
The incident occurred at the Unity Fountain, where protesters had gathered to express concerns over insecurity, economic hardship and governance issues affecting the country, The News Edition reports.
Witnesses said tensions escalated when police operatives moved to disperse the demonstrators, leading to a confrontation between security personnel and participants in the protest.
Security officers reportedly fired tear gas canisters to break up the gathering, causing panic as protesters scrambled for safety.
Amid the confusion, Sowore was said to have collapsed and was subsequently assisted by supporters and other participants at the scene.
Sources close to the protest indicated that the activist was later taken to an undisclosed medical facility for examination and treatment.
The extent of his condition was not immediately known as of the time of filing this report.
The Democracy Day protest attracted several activists and civil society groups who converged on the Unity Fountain to demand action on issues including insecurity, the rising cost of living and governance concerns.
Authorities have yet to issue an official statement regarding the incident or the circumstances surrounding the deployment of tear gas at the protest venue.