MOGADISHU, Somalia - An al-Qaeda-linked Somali militant group has released an audio tape calling for terrorist attacks in a host of countries including Canada.

The tape posted by al-Shabab was allegedly made by an American citizen who blew himself up during an attack on an African Union base in Somalia's capital on Saturday that killed at least 10 people.

The young man urges others to "do jihad in America, do jihad in Canada" and in other parts of the world.

He also urges other youth not to "just chill all day" but to carry out attacks against non-Muslims around the world.

The young man had an American accent and mixed Muslim terminology with American slang.

The U.S. Embassy was not able to comment, but U.S. authorities estimate at least 20 American passport holders have joined the insurgents in Somalia.

About 9,000 African Union peacekeepers supporting Somali government troops have almost pushed al-Shabab from the capital of Mogadishu.

Earlier this month, Kenya opened a second front, sending hundreds of soldiers across the border into southern Somalia.

Somalia has not had a functioning government in more than 20 years.