In this story:

• 'No signs of life'
• Some crash theories ruled out
• 'Black box' recovered
• Related stories and sites

ESCHEDE, Germany (CNN) -- Hopes of finding more survivors from the crash of a German high-speed train dimmed Thursday as rescue workers hauled more bodies from the wreckage, pushing the confirmed death toll to near 100.

The final figure from Wednesday morning's crash could rise as high as 120 as attempts continued to free a first-class passenger car and a dining car that were crushed under the debris of a concrete highway overpass. The overpass collapsed when the derailed train smashed into bridge supports.

About 300 people were injured. Many received first aid on the spot and about 100 remained hospitalized on Thursday, some of them unidentified.

'No signs of life'

The Munich-to-Hamburg train, carrying mostly business people, was approaching the Eschede station in northern Germany when the accident happened about 11 a.m. (0900 GMT/5 a.m. EDT).

More than a day later, there were still no explanations as to why bullet-nosed lead locomotive of the InterCity Express (ICE) train broke loose at 200 kilometers (125 miles) an hour, leaving behind 12 passenger cars and a second locomotive that careened off the tracks and crunched together like an accordion.

The delicate operation of using cranes to remove a heavy concrete slab from the shattered train cars was set to continue until at least late afternoon, but the chances of finding more people alive were fading, even as trained dogs helped rescuers search twisted mounds of steel.

"We can no longer hear any signs of life. The hopes of finding survivors are growing slim," civil defense spokesman Rolf Bartsch said.

Chancellor Helmut Kohl, clearly shaken by the scope of the calamity, cut short a trip to Italy and arrived at the scene early in the afternoon.

Some crash theories ruled out

Rail officials ruled out initial reports that a car belonging to two rail workers caused the accident after it plunged from the bridge into the path of the oncoming train.

"Based on statements from the driver that there were no obstacles on the tracks and the fact that the engine itself was not damaged, we can rule out any causal relationship," said German Railways spokesman Hans-Juergen Frohns.

It appeared more likely that the car fell onto the tracks after the bridge collapsed, experts said.

German Railways has dismissed suggestions the accident was related to work being carried out by its personnel at the site, saying the routine maintenance was not on the track itself but on rail infrastructure to the side of the line.

Aerial photographs show the lead locomotive traveled a further two km (1.2 miles) from the scene of the crash before coming to rest undamaged and uncoupled from the rest of the train.

The first three passenger cars derailed but also passed under the bridge with little damage.

The carnage only started with the fourth passenger car, which was hurled off the tracks by the force of the impact.

The rest of the train's passenger cars were either largely destroyed on impact with the bridge or jack-knifed against each other.

'Black box' recovered

Germany's rail supervisory authority, the Federal Railways Agency, immediately pulled the train's journey data recorder, similar to the "black box" used by airlines, from the wreckage.

Statements from survivors that there was evidence of problems before the crash have led to speculation of a fault with the train.

One passenger described how he felt "a tremendous rattling and shaking" about two minutes before impact.

But it was still unclear why the locomotive had uncoupled from the rest of the train and whether this was a cause or consequence of the accident.

Correspondent Bill Delaney, the Associated Press and Reuters contributed to this report.