David Smith sails across the border, passport in hand

David Smith has an unusual way of crossing the Mexican border into the US - as a human cannonball.

Mr Smith, a professional cannonball, was launched head first across the border between Tijuana, in Mexico, and the US city of San Diego.

His son, also a human cannonball, says Mr Smith is the first person to be fired across an international border.

Mr Smith waved his passport in the air as he sat on the lip of the cannon, before leaving on the brief journey.

'Spatial borders'

The event is the first of a series of public art projects in the two border cities run by the Insite network.

Mr Smith was fired into the sky on Saturday, flying across a rusty border fence from the Mexican beach and landing in a huge net the other side.

I had to make sure to have some kind of official OK high enough up to make sure he doesn't land in the US and go to a federal penitentiary David Smith Jr Day in the life of a human cannonball

Mr Smith said he was inspired by circus performers to explore "the notion of spatial and mental borders".

The US border chief granted Mr Smith special dispensation for crossing into the US in such an unconventional manner.

"I had to make sure to have some kind of official OK high enough up to make sure he doesn't land in the US and go to a federal penitentiary," his son said.

Mr Smith has spawned a family of professional human cannonballs - his son, two daughters and a cousin are all regularly fired from one of five cannons they own.