Searching for clues, as investigators throw a nationwide dragnet over the usual suspects, one question that’s intriguing them is right there at the Churchgate Station from where the seven trains left on Terrible Tuesday: why were the explosives planted in the fourth coach of each train?

In searching for answers to this, investigators are veering towards the explanation that a single unit of terrorists may have planted all the bombs at Churchgate itself and, in a meticulously planned operation, escaped even before the first blast.

Consider the following facts:

• The fourth coach from the front in Mumbai trains always happens to be a First Class coach. But then there are three First Class coaches in a 12-coach train and two in a nine-coach train. Of the seven trains that were hit that day, four had dozen coaches each, the remaining three had nine each. So why did they choose the fourth coach in each train?

• The Sunday Express found that there is a municipality subway on the northern side of the station which is closest to the fourth coach of a train standing on any of the four platforms. All the seven trains on 7/11 left Churchgate, from these platforms, between 5.19 pm and 5.57 pm.

• This subway was unguarded on Tuesday. Today, there were guards but no one was frisking any passengers, there was no metal detector. The subway doesn’t see heavy traffic since most commuters use the main gate for entry and exit.

... contd.