The death toll could be well into the thousands in New York City alone.

Like many U.S. businesses, chip companies in Silicon Valley and other parts of the country clamped down on security. Today's events and the sudden shutdown of all commercial air traffic in the United States also threatened to disrupt the worldwide supply chain for electronics and other high-technology industries.

The U.S. stock markets were closed today and Wednesday. Commercial aircraft in the United States will also be grounded until at Wednesday.

In Silicon Valley, a number of chip companies--including Advanced Micro Devices Inc., Intel Corp., and National Semiconductor Corp.--told SBN that they are still open for business in spite of today's tragedy. But chip companies in Silicon Valley and across the country confirmed that they have curtailed travel, tightened security measures worldwide, and given their U.S. employees the option to leave work in order to attend to family matters.

Today's events will not only impacted daily business operations, but also the worldwide supply-chain as well.

A spokesman for National Semiconductor told SBN that the company has suspended U.S. product shipments via air transport until further notice. "We've suspended all of our product shipments coming in and out of the United States indefinitely," according to spokesman from Santa Clara, Calif.-based National.

AMD, Intel, and others are still assessing the situation.

Most--if not all--electronics equipment manufacturers and chip houses rely heavily on air transportation to ship their products around the world. But given that the U.S. Federal Aviation Agency (FAA) immediately grounded all domestic flights today, chip makers and OEMs said they faced the prospects of some disruptions in the overall supply chain.

"Everybody is in the same boat," according to a spokesman from AMD in Sunnyvale, Calif.

"I would expect that there could be some disruptions with product shipments," the AMD spokesman said. "A lot of our products are shipped by air. If they have grounded all flights, then clearly we will have some impact."

Many companies believe that it's too early to tell what impact today's events will have on product shipments or the supply chain.

Officials from Intel said it's unclear if today's event would impact the company's product shipments. Like AMD, the company relies on air transportation to ship parts from its respective fabs in Europe and North America and packaging plants in Asia.

"It's way too early to tell," according to a spokesman from Intel in Santa Clara. "It's clearly an evolving dynamic situation."

The Intel spokesman did say that the company has tightened security in its worldwide operations, but declined to elaborate. "We've beefed up our security," the spokesman said.

The company is also giving their employees the option to leave work in order to attend to family matters, especially given the fact that schools have been shut down for the day.

AMD, National, and others have implemented similar measures as well.