CHICAGO (WBBM) - Mayor Daley says the best way to keep vandals out is to fence railroads in.  But Metra officials don't agree.

WBBM’s Bob Roberts has the story.

Authorities tell WBBM that whoever pulled spikes from the Metra Electric District tracks on the far South Side a week ago knew what he was doing and was bent on injuring people. 

Daley is not yet sold on the idea that the individual responsible was a terrorist, but he said it makes no sense not to fence in railroads to keep vandals out.

"In order to protect their property, the Park District and other places have to do this," he said.  "They should do it. That should be the long-range goal, really protecting their own property."

But Metra officials said fencing in hundreds of miles of railroad tracks is far different from putting a fence around a Park District pool or a factory. 

The idea has surfaced periodically over the years, and each time Metra officials have dismissed it as impractical and counter-productive. They cite the costs, the difficulty in maintaining the network of fences, and a different safety issue - - what would happen to trespassers trapped inside the fence.

In addition, Metra officials said, those truly bent on creating chaos would not be deterred by a fence. 

Daley responds by saying police need some effort by Metra.

"Chicago Police cannot protect every railroad if you don't have a fence," he said.  "They have a responsibility to protect their own property." 

Metra also has its own police force, which works in conjunction with Chicago Police and other local agencies.  Most major railroads maintain such departments.

The FBI and Metra officials said that the individual used a specially-designed tool to remove some of the spikes from 14 consecutive ties on the Electric District tracks near 100th Place sometime between 8 p.m. Sept. 23 and 10 a.m. Sept, 24, when a track repair crew noticed the spikes missing.

The spikes hold the tracks in place, and the area is one in which trains routinely top 60 miles an hour.

The FBI has conducted dozens of interviews since the attempted sabotage was discovered, and a spokesman said the investigation is one the agency takes "very seriously."