15/09/2017 13:39 BST | Updated 15/09/2017 20:18 BST

Parsons Green Improvised Explosive Device: What We Know So Far

The 'bucket bomb' is believed to have only partially exploded.

LATEST: Islamic State has claimed responsibility for the attack.

The Met Police has confirmed the device that exploded on a Tube train at Parsons Green station this morning was an improvised explosive device (IED).

Some 22 people were injured in the incident, with the majority suffering burns. None are in a life-threatening condition.

Charlie Craven who was boarding the tube at the time of the incident told HuffPost UK: “I got on, I was going to work in the city.

“I stepped in, within two or three seconds there was a massive explosion. There was a massive fireball encompassing the whole carriage.”

Pictures posted to social media show what is thought to be the remains of the IED.

Here’s what we know - and don’t know - about the explosive device.

1) What It Was Made From

The nature of the explosive material within the device is not yet known but it was contained in a large white plastic tub with wires trailing off out of the top.

One witness said it looked like a “bucket of mayonnaise”. 

This itself appears to have been carried in plastic Lidl cool bag 

Wires trailing out of the bucket appear similar to fairy lights, which are a well-known component of bombs from other terrorist plots.

Earlier this year Zahid Hussain, 29, was jailed for a failed attempt to detonate a bomb on a railway line with fairy lights used as “improvised igniters”.

The remains of the device are being examined at a Government facility.

2) It Only Partially Exploded

Police sources have told reporters that the device, thankfully, did not work as it was intended.

Major General Chip Chapman told Sky News: “This doesn’t look like a high-end explosive from ISIS such as TATP (triacetone triperoxide) or, if it was, it failed significantly, the booster or detonator didn’t go off.

“That said of course, the most devastating land-based terror attack in Europe, in Madrid [in an attack carried out by al Qaeda in 2004], had a similar modus operandi.”

“It’s not a high explosive that functioned because the blast and shockwave would have killed multiple people.”

An expert told the BBC that crucially the images of the the device show “deflagration”, the rapid burning of a substance, rather than an explosion which would likely have killed many.

3) It Had A Timer

A security source told CNN the device was intended to cause much greater damage, but cautioned that the investigation is still in its preliminary stages. 


4) We Don’t Know Who Planted It

The mayor of London, Sadiq Khan, told LBC radio: “There is a manhunt underway as we speak.”

The Met Police has appealed for witnesses following the attack.  Officers are urging people with information to contact the hotline on 0800 789 321 or to upload pictures or footage from the scene at

Assistant Met Police commissioner, Mark Rowley, when asked if anyone was in custody, said: “It is very much a live investigation we are following down the lines of inquiry I said.”

Some reports suggest the police have identified a suspect from CCTV images but this has not yet been confirmed. 

5) We Don’t Know When It Was Placed On The Train

Detectives will be referring to London’s extensive CCTV system to determine when and where the device was placed on the train as well as who was responsible. 

There are five stops to the south of Parsons Green - Wimbledon, Wimbledon Park, Southfields, East Putney and Putney Bridge.