Detectives investigating the rush-hour bombing at Parsons Green station on Friday (September 15) have made two further arrests in Wales.
A 48-year-old man and a 30-year-old man were arrested after officers executed a warrant at a second address in Newport at around 5.10am on Wednesday (September 20).
This follows the arrest of a 25-year-old at a separate address in Newport on Tuesday (September 19) evening.
The arrests were carried out by officers from the Metropolitan Police's Counter Terrorism Command, supported by colleagues from Gwent Police and the Welsh Extremism and Counter Terrorism Unit (WECTU).
Searches at the two addresses in Newport are ongoing.
Two other men who were arrested on Saturday remain in police custody, meaning a total five men have been arrested in connection with the investigation to date.
An 18-year-old man was arrested by Kent Police in the port area of Dover at approximately 7.50am under section 41 of the Terrorism Act.
A warrant for his further detention was granted by Westminster Magistrates' Court until September 23.
A 21-year-old was arrested in Hounslow at 11.50pm under section 41 of the Terrorism Act – a warrant for his further detention was granted by Westminster Magistrates' Court until September 21.
Searches at two addresses in Surrey are still ongoing and are expected to last some day but the search at a commercial property in Hounslow has now concluded.
Commander Dean Haydon, head of the Met Counter Terrorism Command, said the investigation continues to be a “fast-moving” one.
“A significant amount of activity has taken place since the attack on Friday," he said.
“We now have five men in custody and searches are continuing at four addresses. Detectives are carrying out extensive inquiries to determine the full facts behind the attack.
"We anticipate that the searches will take some days to complete and may cause further disruption. However, it is important that we continue with these searches and I'd like to thank all those affected for their support, patience and cooperation."
He added: "As police and our partners do all we can to confront the threat, public vigilance remains as vital as ever.
"We urge the public to report any suspicious activity to the police by calling us, in confidence, on 0800 789 321, or in an emergency by dialling 999.
"We are asking the public to look out for anything that seems out of place, unusual or just doesn't seem to fit in with day-to-day life. It may be nothing, but if you see or hear anything that could be terrorist-related trust your instincts, then act, and call us."
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