Thames Water's Swindon office in Kembrey Business Park was locked down for several hours due to a 'white substance' delivered in a package to the office.

More than ten emergency vehicles were called to the site on Tuesday, October 17, 2023, after the suspicious substance raised safety and security concerns.

Experts reportedly travelled almost 40 miles from Porton Down in Salisbury to analyse the 'suspicious' powder, according to a Thames Water employee, while office staff were locked down in the building without explanation.

Several people wearing white hazard suits and gas masks were also seen entering the site, as well as firefighters wearing full protective gear.

Swindon Advertiser: People in gas masks were spotted entering the building.People in gas masks were spotted entering the building. (Image: Newsquest)

The callout appeared to be a false alarm though, as an employee of Thames Water who was trapped in the building confirmed the white substance was 'concrete powder'.

Swindon Police have said:

"We were called to Thames Water, Kembrey Business Park, Swindon around 8.30am this morning (Tuesday) after reports of a suspicious package that had been sent in the post.

"The package contained an unknown white powder.

"The building was put on lock-down as a precaution, and staff were supported throughout the morning.

"The package was deemed not to be harmful, and the scene has been lifted."

Thames Water say they worked closely alongside the emergency services to protect their employees.

"Following the delivery of a suspicious package to our Walnut Court office this morning, we immediately alerted the local fire brigade and police. The police have since confirmed that the package was not harmful," said a spokesperson for the water supplier.

"The health and safety of our employees is a priority and we continue to support staff who were on site this morning."

However, staff trapped inside the building have a different take on the situation, as they say they received no communication about the situation, and employees were left worried and trapped for hours.

"The communication inside Thames has been awful. The press were briefed before those of us stuck inside.

"We have staff stuck outside who aren't allowed to get back in, there are people who need to leave to pick up children soon who are worried that they won't be able to do that."

"People are all very worried and no end is in sight. The only communication we are getting is from the Swindon Advertiser or Facebook," an anonymous employee told The Adver.