The Greater Accra Regional Police Public Relations Officer, DSP Afia Tenge, said checks at the hospitals revealed that seven persons were injured.
According to her, one person, who sustained a gunshot wound in the leg, has been referred to the Korle Bu Teaching Hospital.
She said the Police are investigating the matter to unravel what accounted for the incident.
Some macho men in NSC-branded t-shirts who are suspected to be members of a vigilante group, Invincible and Delta Forces attacked some voters at the Presby school polling station and fired at them.
The National Chairman of the National Democratic Congress (NDC), Samuel Ofosu-Ampofo had alleged that eight persons were injured with two of them being in critical condition.
Speaking to the press, Ofosu-Ampofo said the NDC "felt that this seat is no more important than any single life that will be lost. So, under the circumstances, we have withdrawn our agents.
"We are appealing to all our supporters and sympathisers not to undertake any reprisal attack. We are calling on all our party supporters to remain calm."
He has, however, appealed to supporters of the party to remain calm.
"The NDC is not the body organising the election. We cannot call off the election. We have decided to withdraw our agents.
"We are sending a clear signal to the Commander-in-Chief of the Ghana Armed Forces (GAF) and the President of Ghana, Nana Akufo-Addo that the democracy that we have all fought for, is under siege. Today is a very sad day for democracy and the NDC cannot and will not condone that," he said.