9-7-05 - Radio talk shows and newspapers here buzzed with excitement over news that Mexico, long on the receiving end of U.S. disaster relief, was sending a hurricane aid convoy to help its larger, richer and more powerful northern neighbor.

Carrying water treatment plants, mobile kitchens and supplies to feed victims of Hurricane Katrina, the army convoy bound for Houston will be the first Mexican military unit to operate on U.S. soil since 1846.

The convoy has "a very high symbolic content," said Javier Oliva, a political scientist at Mexico's National Autonomous University. "This is a very sensitive subject, for historic and political reasons."

Large Mexican flags were taped to many of the 35 olive-green Mexican Army trucks and tractor trailers as they rumbled northward toward the border on Wednesday. The convoy was due to cross into Laredo, Texas, early Thursday, President Vicente Fox's office said.

"This is just an act of solidarity between two peoples who are brothers," Fox's spokesman Ruben Aguilar said of the mission.