Great Yarmouth bomb: All we know about Norfolk explosion

Here's everything we know so far about the incident.

How was the bomb discovered?

A contractor working at the development site of the third river crossing in Great Yarmouth found what was believed to be an unexploded device during dredging work on Tuesday morning.

Police were called to the scene at 11.36am and a 400-metre cordon was put in place in the area.

What impact did the cordon have?

Several streets around the site were sealed off, affecting hundreds of households and businesses.

Among the roads closed were Southtown Road, William Adams Way, Tollgate Road and Litchfield Road.

Police at the scene of the bomb (Image: Newsquest)

The cordon was initally expected to be in place until Wednesday, but this was extended due to the complexity of safely disarming the bomb.

Rest centres were also opened to allow residents a place to stay if they chose to leave their homes.

How did emergency services attempt to disarm the bomb?

A major incident was declared by police shortly after the device was found.

An estimated 400 tonnes of sand was used to create a wall around the device in anticipation of the bomb being exploded where it was discovered.

A specialist bomb disposal team from Colchester in Essex was also brought in.

Work then continued over the next few days, with the discovery of nearby gas pipes forcing the original plans to be revised.

However, a further issue arose on Friday when the sand wall built to contain the bomb was compromised by water.

The sand wall being built around the device (Image: Oliv3r Drone Photography)

Norfolk Constabulary's Assistant Chief Constable Nick Davison said: "We understand this has been an incredibly slow process but it’s needed to be for the safety of the public and those involved in disarming the device."

When did the bomb go off?

The explosion of the device, which was not planned, happened shortly before 5pm on Friday - more than 77 hours after it was first discovered.

It went off during slow burn work to disarm the explosives.

All army and emergency service personnel was accounted for and no injuries were reported in the area.

The explosion could be seen across Great Yarmouth and was reportedly heard eight miles away in Hopton, on the Suffolk border.

Assistant Chief Constable Davison added: "As previously stated, there was always a risk of unintended detonation which is why those mitigation measures had been put in place throughout the operation.

"The device detonated shortly after work had started to disarm the device. The approach had been the safest option to disarm the device, however, it always carried a risk of unintended detonation.

"Thankfully, all personnel have been accounted for and agencies are coming together to assess damage to the river wall."