Twitter has frozen a fake account set up in the name of a newly-elected Labour member of the Welsh assembly.
The social networking website agreed to the request by Keith Davies, who suspected the culprit was trying to undermine him with ridicule.
The unofficial account - @KeithDaviesAM - makes several references to spending time gardening and tea drinking.
Mr Davies, who is 70, believes whoever is behind it was trying to depict him as old man not up to the job.
The former Carmarthenshire councillor and director of education, who unseated Plaid Cymru's deputy leader Helen Mary Jones at the election in May, said he believed "figures in the Welsh establishment" were behind the false account.
Plaid has told the Western Mail that it was not responsible.
Llanelli has been a key battleground for Labour and Plaid, with the seat changing hands between them at each of the last three assembly elections.
In May, Mr Davies defeated Ms Jones by just 80 votes, with former Plaid campaigner Sian Caiach taking more than 2,000 votes as an independent.
The unofficial Twitter page appeared shortly after Mr Davies's victory, headed by a photo of him with First Minister Carwyn Jones and a link to the Welsh Labour website.
It features a variety of postings in both English and Welsh, including comments about politics and congratulations to Swansea City on winning promotion.
But several messages refer to "catching up on my gardening", a "well earned cup of tea" and "embracing technology in my old age".
Mr Davies believed it could have taken a more sinister tone, possibly by claiming he supported policies he actually opposed.
"During the campaign there were many letters to the local papers commenting on my age," he said.
"We've been lucky so far - I'm glad I found it when I did.
"Who knows what might have happened - they could have posted messages saying I agreed with policies I don't support.
"My political opponents could have made hay."
While Twitter has frozen the account, previous postings can still be seen on the website.
Mr Davies said Dyfed-Powys Police were asking their IT specialist to investigate and see if they could identify the person responsible.
He set up his own Twitter account - @Caedelyn - shortly after being selected as Labour's assembly candidate for Llanelli in April 2009.
However, he has not posted any new messages since February 2011.
"I stopped using it as I didn't want my opponents following my every move during the election campaign," he said.
"I may start using it again, saying what I've done rather than will be doing."