A man has been arrested in connection with a “suspicious item” found in Watford.
Areas remain cordoned off and roads are still closed to traffic while further assessments are made, Hertfordshire Police have said.
They are appealing for information to find a female dog walker who they believe may have important information about the incident.
A statement on the constabulary’s Facebook page said: "The woman was walking through Watford Town Centre around the time of the incident and may have seen the suspicious device prior to it being reported to the police."
Earlier today, police asked people to avoid Watford Town Centre after the item was found in Market Street at 11am. The incident was thought to be a bomb scare.
Market Street, the High Street and the Ring Road were closed off while a disposal team destroyed the device.
“An Explosive Ordnance Disposal team is currently in #Watford town centre assessing the situation,” tweeted the police.
An Explosive Ordnance Disposal team is currently in #Watford town centre assessing the situation. Please avoid the area until further notice— Herts Police (@HertsPolice) June 18, 2015
They later said “a suspicious device [had] been safely destroyed following a controlled explosion by bomb disposal experts”.
The Watford Observer reported that bystanders said they heard “what sounded like a gunshot”, when the item was destroyed.
UPDATE - #Watford incident: a suspicious device has been safely destroyed following a controlled explosion by bomb disposal experts.— Herts Police (@HertsPolice) June 18, 2015
UPDATE - #Watford incident: a man has been arrested in connection with the incident and is being taken into police custody.— Herts Police (@HertsPolice) June 18, 2015
The police later arrested a man in connection with the incident. Pictures on Twitter showed that the man was wearing a burka.
The Evening Standard reported that the man was carrying two rucksacks filled with children's books.
Members of the public have been posting on Twitter throughout the day.
In a statement, police said: "Experts remain at the scene making further assessments and follow up enquiries. This work is likely to continue for some while and as a precaution cordons and road closures in Market Street and the High Street will remain in place. The ring road has also been closed to traffic." Reuse content
This is a white Man in a burka with a suspicious package in Watford apparently, bomb squad called pic.twitter.com/bY9Sbyljym— Daniel Gover (@dangover2) June 18, 2015