Gravesham council has closed the reception area of the Civic Centre after a hand grenade was handed in.
The Civic Centre has been evacuated on advice of Kent Police.
The Conservatives have comfortably held Gravesham - a traditional 'bellweather' seat that tends to reflect the overall result in the country.
Sitting MP Adam Holloway polled 23,484 votes and secured a 48.6% shared.
Labour were second and UKIP third.
A property owner who ignored a court order to improve a house and gardens in Gravesham has been fined £5,000 at a second hearing in Dartford.
Henry Robinson, aged 69, from Dartford, admitted failing to comply with a notice under the Town and Country Planning Act 1990.
The notice required him to improve the neglected and rarely occupied property in Mulberry Close, Meopham both to the building and the front and rear gardens.
He had been fined £250 last November and the deadline was extended to March this year to do the work.
This time the court fined him £5,000 with £245 costs.
The property has been in disrepair for some time and every opportunity was given to Mr Robinson to make the improvements without the need for formal legal action.