LAGOS, May 2: Seven people were shot dead in clashes with Nigerian police during May Day protests on Friday against military leader Sani Abacha in the south-western city of Ibadan, witnesses said.Several other people were wounded while 17 vehicles were set on fire during the clashes which erupted in various parts of the city, the witnesses said. Police also arrested six militants of the United Action for Democracy, an umbrella for Oppn and human rights groups which had called for the May Day demonstrations aimed at bringing down the regime.