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From the very first moments of this American tragedy, security at the border has been extremely tight.

BORDER TRAFFIC Check delays at the Calif.-Mexico border

Most commuters Wednesday said they understood the reason behind the extra security, and didn't mind the delays that have come as a result.

"Inspections are more intense, I guess that's the way it should be," driver Raul Ochoa told 10News.

U.S. Customs is on its highest state of alert, according to 10News, pushing the wait time for cars crossing the border well into the four-hour range.

"I came in around 8:30 this morning. I go through a special lane, where it's usually a five-minute wait," commuter Veronica Acevedo. "There was a 150-car wait."

Many border crossers decided to just walk across, but were still met with a long line. The usual 10-minute wait to walk across the border was extended to around an hour and a half.

Additional customs personnel and security equipment have been brought in, to ensure that rumors of the border being closed don't come true.

"I'm just concerned that if I go in (to Mexico), I won't be able to come back out. I have a dentist appointment in Tijuana. He's a wonderful guy, I've been there before, but now I'm a little concerned," Shelia Trevett told 10News.

The concern of possibly not being able to get back into the United States is so great, that some visitors have decided to cancel their plans to travel south. Luis Cabera drove down from Los Angeles to bring relatives to Tijuana, but changed his mind at the last moment.

"We don't want to be stuck there for so many hours. Who knows what could happen?," Cabera said.

And that heightened concern is making business difficult for the people accustomed to the usual volume of border travelers.

"Everything is down, everyone's scared. They want to stay home where it's safe," taxi driver Jesus Martinez said.

Border officials told 10News that there are no plans to close any California border crossings, but have not ruled out the possibility.