A Piece of Ground Zero in the Rio Grande Valley

U.S. Customs and Border Protection agents stood in silence, as all ports of entry in Brownsville stopped operations at 7:46 Sunday morning - the exact time the first World Trade Center tower was attacked on 9/11.

Port Director Michael Freeman said, "that was a day which defines the greatest challenge for the new America - the challenge of global terrorism."

Freeman said the deadly attacks stripped Americans of security. Ten years later, he said that security is stronger than ever, with federal agencies like U.S. Immigration and Customs Enforcement, U.S. Border Patrol and CBP all working together.

"By having that one voice, we have one fight against our common enemy, Freeman said. That enemy is the prevention of terrorist and elements of terrorism from entering the united states."

On South Padre Island, a moment of silence served to honor the thousands of lives lost on 9/11. Officials then unveiled a steel beam recovered from Ground Zero. It will be housed at the SPI fire station.

"It's a piece of history, Fire Chief Burney Baskett said. The impact of going up to it and actually touching it - that piece of steel - it's sometimes overwhelming. There is a close connection " we firefighters have a bond."

Sara Fuller took a picture of her daughters next to the historic piece. She's married to a fire fighter and said the steel beam reminds her of the sacrifices made by hundreds of firefighters on September 11th, 2001.

"To have it means a lot to me just to be able to look at it to remember and to never forget the sacrifices that the 343 fire fighters made, Fuller said. (Also), all the police officers and just the citizens that fought for their life to get out."

Events to honor 9/11 victims continued at the University of Texas at Brownsville.

President Dr. Juliet Garcia compares the effects of the 9/11 attacks to those of the attack on Pearl Harbor and the assassination of President John F. Kennedy - meaning life in the U.S. will never be the same.

"There was a life we all knew before 9/11, and then a whole generation's life that has changed after that event," Garcia said.