Homeland security officials announced new steps Friday to protect the U.S. rail system from terrorist attack.  VOA National correspondent Jim Malone reports from Washington.

A maintenance worker walks past the company logo on the side of a locomotive in the Union Pacific Railroad fueling yard in north Denver

The focus of the new security measures is on preventing terrorists from exploding rail cars carrying dangerous chemicals like chlorine.

Homeland Security Secretary Michael Chertoff announced the plan at a Washington news conference.

"The biggest danger I think we are concerned about is the possibility of a terrorist blowing up a [rail] car, which causes dangerous chemicals to be emitted into the air that will affect people's respiratory system, where people are going to be breathing chlorine, or breathing anhydrous ammonia," he said.

The security measures include inspections of rail cars and keeping them in a secure area when not in use.  Each railroad will designate a security coordinator, who will receive terrorist threat information from the government.  The government will also have the ability to track individual rail cars carrying hazardous materials.

Secretary Chertoff says rail systems are being asked to minimize the time when rail cars carrying dangerous chemicals are standing still.

"We want to reduce and drive down that standstill time, because the vulnerability of the system is greatest when the [rail] car is sitting still, and there is the least vulnerability and risk when the car is moving rapidly," he added.

Some Democrats in Congress are already complaining about the new regulations, saying the plan is late in coming and does not do enough to tighten rail security.

On another issue, Secretary Chertoff defended his department's decision to abandon for now a program to check the identities of visitors leaving the United States by land.  Exit checks for those traveling by air will go forward.

A government report said it would take five years to10 years to develop the technology that would create a departure system for foreign visitors who are leaving the country by land, a system that would not result in major delays at border check points.

Secretary Chertoff said the government remains committed to the program, but it may take years to implement.

"Not only the cost of finding technology, but the unbelievably long lines that you would see at the border crossings, if we required all the people leaving the country by land going into Canada to stop to give a biometric print," he said.  "You would see lines that are 10 or 15 miles long."

Chertoff says the entry portion of the program is working well, and includes digital scans of fingerprints to identify foreign visitors.

The program, known as U.S. Visit, was implemented following the 2001 terrorist attacks to better screen for suspected terrorists entering the United States.