Police staff in West Sussex – including 999 call handlers – are to go on strike for 24 hours over pay.
The strike, which will involve members of UNISON, will start at one minutes past midnight on Monday December 22.
The action has been called in support of a campaign to re-open pay talks to improve the 1 per cent pay offer made to staff for 2014.
Staff from the Hampshire force will also walk out for 24 hours.
A spokesman for UNISON said the strike would be followed by four weeks of action, short of strike action, from Monday January 5 2015 to Sunday February 1 2015, in the form of a ban on voluntary overtime.
UNISON members in the police service work in jobs such as 999 call takers, police community support officers, scenes of crime officers, fingerprint experts, financial investigators, detention officers, crime reduction officers, crime analysts, enquiry desk officers, trainers, criminal justice clerks, and a wide range of vital operational and organisational support roles.
UNISON regional organiser Caroline Villiers said: “Police staff have been hit hard by the cost of living crisis.
“Since 2010, two years of pay freeze and a below inflation pay deal last year has seen the value of their pay decline by 13 per cent.
“It is rare for police staff to take industrial action and the strike is a clear sign that they’ve had enough.
“For many of our members it will be the first time they have ever taken industrial action over pay.
“The last time police members struck in relation to pay was 25 years ago in 1989.
“Police staff have had a raw deal. All we’re asking for is fair pay. Our members’ contribution to community safety is immense and it needs to be reflected in their pay.
“Earlier this year, we asked for a 3 per cent, or £500, increase (whichever is the greater) on police staff pay points.
“The police employers responded with another 1 per cent offer which is just not acceptable.
“We are calling on the police employers to return to the negotiating table to improve the current pay offer in order to stop this dispute from escalating.”