CONCORD — A former member of Israel's counterterrorist unit taught BART's SWAT Team how to tackle and disarm potential suicide bombers during four days of intensive training exercises that transit officials say are crucial to protecting riders.

A U.S. State Department study found that nearly 45 percent of all terrorist attacks worldwide have been against ground transportation.

Last July, 56 people were killed and 700 others were injured when four suicide bombers set off a series of bombs on London's public underground trains and on a bus.

Two years ago this week, 191 people were killed and 1,741 more were injured during terrorist attacks on Madrid's morning commuter trains. Police arrested 116 in connection with the deadly bombings.

BART officials know that the hundreds of thousands of people who ride the trains everyday are also at risk for terror attacks.

"This system has been identified as a target," said BART Police Lt. Dan Hartwig, head of the SWAT team. "We have to be prepared. The ridership has to be prepared. And we will take those steps to make sure that we are."

BART spent an undisclosed amount of money to hire Aaron Cohen, a former member of the Israel Defense Forces Special Forces Counterrorist Unit who now runs a Los Angeles-based security company that uses Israeli military tactics to train members of local, state and federal agencies.

Cohen has worked with the FBI, the Los Angeles International Airport Special Response/Hostage Rescue Team, Houston Metro Swat Team and the Los Angeles County Sheriff's Department.

And now BART.

Cohen spent four days last week training members of the BART SWAT Team how to take down a suicide bomber without using a weapon.

"The goal is to bring as much damage (to the person) in as short of time as possible," he said to a group of reporters watching the last day of the drills on Sunday.

That meant teaching the SWAT men to grab the "suicide bomber" below the knees, push him to the ground, sit on his back, and quickly lock his arms be-hind his back.

My goal is to give them a combat doctrine to help them reduce the risk to themselves and to the people riding the train, Cohen said.

The training was just one piece of the transit agencys anti-terrorist plan. BART still has identified $215 million for detection and protection security enhancements, and operational and staffing strategies.

It also needs an undetermined amount of money for chemical and biological detection technology, according to written information about BARTs anti-terrorism efforts.

Police patrol the 43 BART stations and trains during all operating hours and during the majority of down hours, too, Hartwig said. The SWAT team is called in when the terror alert level is raised to orange or when there is a potential problem on a train or in a stations, BART officials said.

During the training, the SWAT members were also taught what to look for when identifying a potential terrorist. People who avoid security, sweat profusely, clinch a bag too tightly or dress in clothes for the wrong season might be suspicious.

But police cant be the only ones on the lookout, Cohen said.

With terror we have all learned that we are all responsible for the protective layers, he said. If any of those red flags go up, let security know.