Prime Minister Narendra Modi sat calmly during a 20-minute security breach when his carcade was stuck on a flyover in Punjab, exposed to nearby buildings while a 10-km distance from the Pakistan border made it vulnerable to drone-delivered explosives.

As a Supreme Court-mandated committee is now set to inquire into the unprecedented security lapse, central government sources pointed to a worrying sequence of events that have been briefly shared with the court and will be put before the panel in much more detail.

The blockade was completely unexpected as no warning was given by the lead Punjab Police escort that was 3-4km ahead of the main PM carcade -- something that is puzzling the security establishment. This resulted in the carcade pulling up within 100 meters of protestors said to be farmers opposed to the recently rescinded farm laws, placing the PM's party in range of a sniper or even stone pelting, say sources.

A sequence of events of the day compiled by official agencies says that cars reserved for the state DGP and chief secretary were part of the cavalcade but the officials never turned up. Chief Minister Charanjit Channi had not received the PM, and it was surprising that neither of the two officials showed up either.

The key points raised are:

The argument that it is the SPG's duty alone to secure the PM flies in the face of SPG rule book chapter 1, rule 1, that the "overall responsibility for ensuring the safety of the PM rests with the state government and responsibility for providing proximate security rests with the SPG as per the SPG Act, 1988." The buck for perimeter security stops with the DGP.

The claim that the Punjab government and police were not informed of the road journey once weather ruled out the chopper ride is incorrect, say sources, as the advanced security liaison (ASL) by SPG and Punjab administration-police discussed the contingency plan for a road journey from Bathinda to Ferozepur in detail.

In light of intelligence inputs regarding sabotage possibilities, strong police deployment was emphasised in the ASL. Later videos emerged showing cops sipping tea with protestors. Since the road plan was not known to just a few, how was it leaked? And if the protestors just happened to be there, how did Punjab Police give the green signal? These are just some of the questions emerging from the breach.

The SPG role is defined at proximate security. Perimeter arrangements are in the hands of the local police. A contingency rehearsal for the road plan was in fact carried out on January 4. The road journey was not sudden: the director SPG discussed the possibility of a safe and secure passage to Ferozepur.

Internal documents of the Punjab Police show that there was apprehension of roadblocks and the need for a traffic diversion plan. There is a mention of the need to keep a watch on the movement of some farmers and that they should not be allowed to disrupt the campaign rally in Ferozepur.

Punjab Police control room did not inform the pilot of the PM's motorcade that the road was blocked, if this had happened, the situation where Modi was stuck on a flyover would have been averted. Senior police officers at the site could not clear the crowd which swelled to potentially dangerous proportions.

While the SC-appointed committee will examine the claims and the records pertaining to the security breach amid political charges and rebuttals, the events of the day show that the Prime Minister was exposed to an unacceptable -- and potentially serious -- security risk.

Follow us on Facebook, Twitter, YouTube & Instagram to never miss an update from Fortune India. To buy a copy, visit Amazon.