DETROIT (AP) — A businessman who held contracts at Detroit's convention center says he personally delivered thousands of dollars in cash to then-Mayor Kwame Kilpatrick.

Karl Kado (KAY'-dough) told jurors Monday that he passed $5,000 to $10,000 to Kilpatrick "three or four times." He says he also delivered money through a Kilpatrick aide and separately paid $200,000 to $300,000 to Kilpatrick's father, Bernard.

Kado says he felt like a "hostage" and had to pay to keep his work at Cobo Center.

Kado is a key witness at a corruption trial, which began in September. The Kilpatricks and a third man are accused of extortion, bribery and other crimes.

Kado says Kwame Kilpatrick was a friend but he gave money because he was the mayor with power over contracts. Kilpatrick quit office in 2008.