Sept. 20 (UPI) -- Two more potential suspects have been arrested in connection with the terrorist attack on a London subway last week, London's Metropolitan Police said Wednesday.
The unidentified men, ages 48 and 30, were arrested under Britain's Terrorism Act in Newport, a city in Wales.
Another man, 25, was detained in Newport Tuesday in a separate arrest.
The total number of arrests linked to the bombing is now five -- including two who were detained last week.
The explosion of a homemade bomb, left in a shopping bag, occurred at London's Parsons Green subway station last Friday morning. Thirty people were hurt, mostly with burns.
"This continues to be a fast-moving investigation. A significant amount of activity has taken place since the attack on Friday," said Cmdr. Dean Haydon, chief of the Metropolitan Police counterterrorism command. "Detectives are carrying out extensive inquiries to determine the full facts behind the attack."
Police added that searches of two houses in Surrey, a county near London, are expected to last several more days.
The arrests suggest that the incident was the work of a network of people and not of an isolated individual, BBC News reported Wednesday.
The 21-year-old man arrested Saturday has been named as Yahyah Farroukh, a Syrian-born former British foster child.