British police probing an alleged plot to blow up as many as 10 US-bound airliners have gathered "substantial material" in their investigation, Home Secretary John Reid said on Sunday, as police continued to question 23 suspects and conduct searches at locations across the country.
Reid, Britain's senior law and order official, indicated some individuals could be charged with criminal offenses in the next few days as a result of the inquiry but refused to disclose specific details, in keeping with the tightlipped nature of the operation.
"Police and the security authorities are content that their investigation is rewarding substantial material which would allow them to take forward the judicial process," Reid said in an interview with ABC-TV's This Week.
"The police and the authorities are convinced that there was an alleged plot here. They have intervened. And in the course of the next few days, we'll wait and see what happens in terms of charges," the home secretary said.
Investigators have until today to question two suspects, and until tomorrow to interview 21 others. Officers may seek to hold the suspects for a maximum of 28 days before charging them. To keep suspects they still wish to question in custody, police must ask a judge to extend the current deadlines.
London's Metropolitan police said yesterday it could not confirm if officers would make any application today to continue to detain the two suspects due to be released under the current deadlines.
In Pakistan, law enforcement officials are continuing to interrogate Rashid Rauf, a Briton of Pakistani descent, over his alleged key role in the plot, officials said.
Interior Minister Aftab Khan Sherpao said British police were conducting inquiries in Pakistan, but were not involved in the questioning of Rauf.
New security measures threw Britain's airports into chaos in the days after arrests were made on Aug. 10, but officials at London's Heathrow Airport -- Europe's busiest, and the worst affected hub -- said on Sunday that most flights were now unaffected.
British Trade and Industry Secretary Alistair Darling said airport security restrictions were "proportionate" to the threat level, which stands at severe -- the second most serious level.
He said a meeting has been scheduled within "the next week or so" to listen to concerns from airport operators, who claim the government demanded too many time-consuming security checks in the aftermath of the arrests.
"Unfortunately it was necessary, because of the intelligence we received, to step up security," Darling told BBC television on Sunday.
"But I hope that in the next few days we can make sure that the system is manageable, is proportionate," he said.
Tighter security regulations on passengers carrying hand luggage and liquids onboard planes were ushered in at airports after Reid said police had foiled a plan to "bring down a number of aircraft through mid-flight explosions."
It was revealed by US officials that authorities believed the alleged terrorists planned to detonate liquid explosives aboard the aircraft.
When asked if that was possible, Reid told the TV program that it was "relatively simple to make quite an effective bomb" aboard an airplane.
"It is a constant search by the terrorists to find ways around our restrictions, around our surveillance, around our security means, around our airports and other transportation restrictions, in order to try and defeat our counterterrorism and to inflict the sort of damage that we've seen before," Reid said.