A 10-member CBI team, which is in Odisha to probe the triple train accident, inspected the tracks, signal room and talked to railway officials at Bahanaga Bazar station in Balasore district on Tuesday.
The CBI probe was recommended by the Railway Board on Sunday.
In all, 278 people have lost their lives and over 1,200 injured in the June 2 train crash.
A forensics team, which is accompanying the CBI officials, also spoke to signal room employees and sought information about the functioning of different equipment.
The CBI will probe criminal angles into the accident as the Railways suspect sabotage and outside intervention behind the accident.
Khurda Road Division DRM Rinkesh Roy had suspected ‘physical tampering’ of the signaling system.
The Central agency had taken over Balasore GRP case No. 64 registered by Odisha Police on June 3, a day after the accident.
"The CBI will probe all aspects. It is gathering information and the Railways will extend full cooperation," said South Eastern Railway chief public relations officer Aditya Choudhury.
On Monday, the Chief Commissioner of Railway Safety, SE Circle, Shailesh Kumar Pathak had visited the spot and spoke to people about the accident as part of his probe.
The reason behind the accident will be known after completion of investigations by CBI and CCRS, an official said, adding that the GRP in Balasore had registered an FIR and is also probing into the accident.
The Coromandel Express crashed into a stationary goods train, derailing most of its coaches at 7 pm on June 2.
A few coaches of Coromandel toppled over the last few coaches of the Bengaluru-Howrah Express which was passing by at the same time.
Of the 278 dead persons, 177 bodies have been identified and handed over to their families.
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