The Socio-Economic Rights and Accountability Project, SERAP, has asked President Muhammadu Buhari administration to promptly investigate the reported attacks on the Labour Party presidential candidate, Peter Obi, or face a legal battle.
SERAP issued this warning to the government in a statement on Wednesday.
The statement said, "We'll take legal action if the perpetrators are not immediately arrested and prosecuted."
Meanwhile, the presidential campaign council of the Labour Party reported that the convoy of Obi was attacked two times in Katsina State on Monday.
A spokesperson for Obi/Datti Presidential Campaign Council Diran Onifade said Obi was attacked by hoodlums on his way to the airport after his rally in Katsina.
According to Onifade, some yet-to-be-identified hoodlums hurled heavy stones at the driver's side of Obi's vehicle on his way to the airport.
He said the stone caused heavy damage to the vehicle, though Obi and those in the car with him escaped without sustaining injuries.
The spokesperson added that another set of hoodlums had earlier attacked the campaign convoy with stones in front of the Katsina stadium.
He said the attack left several vehicles, including that of the official stage crew damaged.
"Our candidate had met with women in a town hall and then held a hugely successful Rally at the Muhammad Dikko Stadium.
"However, on his way to the airport, hoodlums attacked the car our candidate was riding in with heavy stones from his driver's side causing substantial damage to the vehicle.
"To the glory of God, Mr. Obi and other occupants of the car were unhurt.
"Subsequently another set of thugs also threw stones outside the stadium which damaged several vehicles including that of our official stage crew.
"The two incidents taken together make us suspect that the attacks may have been premeditated at the behest of desperate politicians who had been deluding themselves with the false claim that they had the northwest locked up but are now shocked by the show of force of the Obidient movement in the region.
"While thanking the good people of Katsina who came out en masse to support our campaign yesterday, we call on security agencies to investigate this matter to forestall future occurrences," the Campaign Council said.