This morning (Friday 11 March) officers from Greater Manchester Police, alongside Nottinghamshire Police attended an address in the Hucknall area of Nottingham and arrested a 57-year-old woman on suspicion of malicious communications.
She remains in custody for questioning.
The arrest forms part of an ongoing investigation - codenamed Operation Octant - into malicious communications sent to a woman in her 40s in the Ashton-under-Lyne area.
This latest arrest relates to abusive emails sent to the woman on Saturday 19 February.
Five arrests have been made so far as part of the investigation, resulting in three men being charged and one man being convicted.
Enquiries remain ongoing.
Anyone with information should contact police on 0161 856 9262 via 101 or our LiveChat function at www.gmp.police.uk. Alternatively details can be passed via the anonymous charity Crimestoppers on 0800 555 111.
If you have been a victim of hate, don't suffer in silence. Visit gmvictims.org.uk to access victim support and information. You can report hate crime online, via www.gmp.police.uk or by calling 101.