Police are searching the former Bonhill home of convicted paedophile Norman Duncan.
Officers entered Duncan's former Ladyton property this morning where he lived before he was jailed for five years in 2016.
The 73-year-old was found guilty at Dumbarton Sheriff Court of six charges of historical sexual abuse against young girls in the 1960s and 70s.
Police confirmed a house was being searched as part of an ongoing invesigation.
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However, they would not provide any further information.
In July last year, police confirmed they had spoken to Duncan as part of their fresh enquiry into the disappearance of 17-year-old Mary Duncan, who went missing 43 years ago.
It is understood officers arrived at Ladyton this morning (April 3) and entered a property in the estate where they are currently carrying out a search.
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A number of police vans and forensic teams remain at the scene while a search is carried out.
One neighbour, who lives near the property, said: "I looked out and saw the police van this morning and more and more police have arrived and they are currently going into the house with their white forensic suits on.
"They are all out in the streets and going in and out of the house with cameras.
"I noticed a few plain clothes officers too so it looks like there is something serious going on."
A Police Scotland spokeswoman said: "Police are currently searching an address in Ladyton, Alexandria, as part of an ongoing investigation."
Updates to follow.
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