Plaid Cymru Assembly Member Simon Thomas has resigned from the party and the Assembly after being arrested on suspicion of possessing indecent images.
He was the Assembly Member for the Mid and West Wales region.
Dyfed Powys police confirmed that they had arrested a man from Aberystwyth and released him on bail for 28 days.
“An individual from Aberystwyth has been arrested on suspicion of possessing indecent images,” they said in a statement.
Former Llanelli Assembly Member Helen Mary Jones, as the next name on Plaid Cymru’s Mid and West Wales region list, is expected to become an Assembly Member in his place.
She tweeted: “In something of a state of shock. I have now got some big decisions to make in the next few days. I won’t be on here a lot. Thanks for good wishes already recieved.”
Vicky Moller is the third-placed candidate on the Plaid Cymru Mid and West Wales list.
Plaid Cymru Chair, Aun Ffred Jones said that he had received Simon Thomas’ resignation as a member of the party.
“We are aware of a police investigation into allegations of a serious offence,” he said.
“Due to that ongoing investigation, it would not be appropriate to comment further at this time.”
The Assembly’s Llywydd, Elin Jones, said that she had received Simon Thomas’ resignation letter as AM for Mid and West Wales.
“The Results Officer for the region has been informed, and we are working with each other to administrate the election of a new elected representative.”
The 54-year-old married father-of-two was MP for Ceredigion between 2000 and 2005.
After losing his seat in 2005 he became a development manager with Technium in Pembrokeshire before becoming a special senior adviser to the Welsh Government.
He was elected as AM for the Mid and West Wales region in 2011.
Simon Thomas was Plaid Cymru’s spokesperson on the Environment and Rural Affairs. He was due to launch a report on developing Wales’ economy at the Royal Welsh Show today, a report which had his picture on the cover.
He has deleted his website and his Twitter account.