Thread by @HKaaman

[Thread] At 6AM on October 8, a massive explosion collapsed sections of the Kerch road bridge & also damaged the adjacent railway bridge, severely incapacitating Russian logistics to and from Crimea. Here's my take on the attack, and why It was likely a suicide car bomb (SVBIED)

Satellite images released in the days since the attack show the extent of damage, with the railway tracks still inoperable and a single flimsy lane on the road bridge. At the outset, there were two competing theories;
- SVBIED on the bridge
- A boat-based VBIED under the bridge

I initially didn't want to rule out the latter theory, mainly because of how insane the bridge SVBIED theory sounded. However, there are multiple reasons why a boat-based VBIED could not have been used:

A second CCTV perspective was used as 'evidence' of a boat being driven under the road bridge just as the detonation happened. The waves in the bottom right corner of the footage were identified as proof of a boat's wake, despite no boat being seen.

Although a likely Ukrainian USV fitted with explosives (remote-controlled suicide boat) was discovered by Russian forces on the shores of the black sea near Sevastopol late last month, it was likely intended for use against ships. It's too small for Kerch news.usni.org/2022/10/11/sus…

Estimates put the weight of the explosives used in the attack at around 1000-2000kg (2,200-4,400lb), which is far too heavy for the seized 'suicide' boat.

Besides, if it really was a boat that detonated, there would be extensive damage, blast marks, as well as soot on the underside of the collapsed sections of the road bridge. There was none. The lack of water disturbance in the 2nd CCTV video also speaks against a boat being used.

This leaves just one explanation: A powerful SVBIED detonating on the bridge. There are many signs pointing to this. Large soot marks on top of the road bridge + lateral blast marks & bent railings/lampposts all indicate something detonated on the bridge

Furthermore, this picture seems to show a very noticeable depression in the section of the road bridge directly adjacent to where the SVBIED detonated, as if a powerful force (e.g. an SVBIED) pressed down from on top.

Now that we've established something detonated on the bridge, let me explain why and how an SVBIED was used in order to neutralize the bridge. First, this was likely not a traditional SVBIED where an ideologically convinced suicide bomber sacrificed his life for the cause

SVBIED attacks don't always require a willing driver. The IRA popularised so-called "proxy bombs" where people were coerced under threat to drive SVBIEDs toward hostile targets, where they were detonated remotely upon arrival en.wikipedia.org/wiki/Proxy_bomb

However, this was likely an 'unwitting' SVBIED. The 52-year old driver of the lorry that detonated, Makhir Yusubov, likely had no idea what was going on. CCTV footage shows Russian soldiers inspecting the SVBIED prior to Yusubov crossing, with no one raising any alarms

The real alarm bells are represented by the fact that the truck was crossing the Kerch bridge from Russia to Crimea. Does the SBU have intricate SVBIED manufacturing facilities inside Russia proper? Probably not. The likely answer is quite ingenious

How do you transport large quantities of explosives without raising too much suspicion? Ammonium nitrate (fertilizer). Although the leading theory is that the explosives are AN-based, they were likely combined with an accelerant from the start

The explosives were likely mixed and concealed in Ukraine, before being transported/smuggled into Krasnodar, Russia on lorries via the Caucasus. The driver reportedly got an online order to transport AN from Russia to Crimea --> efe.com/en/latest-news…

Assuming that Ukraine had operatives in place, a front company in the Krasnodar area could've contracted the now deceased driver for a shipment to Crimea, loaded the goods on the truck, and also connected a remote detonation mechanism to the already boosted ammonium nitrate

Hence, an 'unwitting' SVBIED. The lorry detonated just after the start of an ascending incline on the road bridge, igniting train cars on the above railway bridge as well. Either of these (incline/train) could have been used as target reference if the detonation was RC-operated

Some people are putting forth long-range fires as an alternative explanation, but this doesn’t make sense. ATACMS (which Ukraine doesn’t have) have an individual payload of 100kg, just 5-10% of most estimates of the size of the actual detonation. This is not the Antonovsky bridge

Some new footage of the exact point of detonation, which is located on the only section of the Kerch road bridge that cracked in two. The shorter end is bent inwards with clear surface damage and one end of a larger hole straight through visible. No visible damage under bridge.