Eyewitnesses say no fewer than twelve persons, including four policemen, on Wednesday collapsed in Katsina state at the General Muhammadu Buhari (rtd) presidential-bid campaign rally which held at the Polo Ground.
The event which was scheduled to commence at 10am did not start until around 4.30pm.
An eyewitness tnoted some of the victims had been standing for hours under the sun, and that the heat and stress must have taken a toll on them.
He also said there were cases of people collapsing among the crowd that had gathered, but some of them were revived by sympathisers who fanned and poured water on them.
Most of the collapsed victims were standing close to the podium where key members of the All Progressive Congress, APC, were scheduled to speak to a mammoth crowd and they were taken to hospital for treatment after they collapsed.