SEATTLE -- Officials say investigators will focus on three possible causes for a weekend crash of the Seattle monorail: operator error, signal malfunction or communications problems.

The 43-year-old elevated line's only two trains remain stuck on the tracks in downtown Seattle. The historic Monorial's trains loudly side-swiped to a screetching halt, wedging one into the other Saturday night.

The area underneath the line has become a tourist attracktion where the curious are craning their necks and snapping their pictures at the train wreck jammed 30 feet above street level.

"Truly, I was hoping just judging from the television pictures that it wasn't quite that bad," said longtime rider Alexandra Dunn as she gawked at the mangled cars.

The cars seem to lean over a street full of shopping traffic while engineers wonder how to use cranes to seperate the trains and somehow get them back to the mainenance area at Seattle Center.

No one knows when the trains will be fixed and running because this has never happened before.

This is a pinch point, a narrow area within the track that has always been known that you can't pass the two trains at the same time," said Perry Cooper with the Seattle Center.

As they figure out how the two drivers ran into each other, monorail fans are disappointed.

"It's too bad, because y'know, it's the busiest time of the year for the monorail. So I hope they get it fixed pretty quick." said monorail rider Ron Martorano.

Monorail officials say help is on the way for shoppers and others who rely on the monorail.

This is the first time both rail lines have been down.

Officials are now trying to line up buses to shuttle passengers between the Seattle Center and Westlake Center. They tell us they may strike a deal with a private bus line or just encourage riders to use a Metro bus.