Complex sentence: The home-made device was the third and final bomb which was planted by extremist David Copeland, who first targeted the community of Brixton on Saturday, 17 April 1999 and then Brick Lane on Saturday, 24 April 1999.
Split into simpler sentences: The home-made device was the third and final bomb which was planted by extremist David Copeland in 1999. He first targeted the community of Brixton on Saturday, 17 April 1999 and then Brick Lane on Saturday, 24 April 1999.