In Nigeria, two American and two Canadians who were kidnapped by gunmen in northern state of Kaduna this week were freed today. <br/>'<br/>Kaduna state police spokesman Muktar Aliyu said armed forces had launched a manhunt for the four after they were seized on Tuesday evening by kidnappers who shot dead two of their police escorts. He said they have been rescued today and are now with their embassies.<br/>'<br/>The four were on private business in Kaduna when they were snatched on the road from the town of Kafanchan to the state capital of Abuja, the latest abduction in Nigeria involving foreigners.