The Communication Workers Union has announced that its first 24 hour strike in the run up to Christmas will take place on Monday 10 December.
Postal workers at the Royal Mail depot in Mead Street in Bristol will take action between 0001 hours and 2359 hours.
It means there will be no deliveries to the BS4 and BS14 areas that day.
Talks between the CWU and Royal Mail broke down today in a dispute over workloads at the South Bristol Depot.
More top news
A teenage boy is also in hospital. Police believe both had suffered adverse reactions to an unknown substance.
Sunshine all day tomorrow and warm week ahead
Lovely and warm with highs of 23 and 24 degrees. Hottest on Wednesday.