The 12th suspect charged in the alleged plot to down U.S.-bound airliners faced a court appearance on Friday.

Umair Hussain, 24, was charged Thursday with having information about a possible terrorist act and not disclosing it, Metropolitan Police said.

Of those charged so far, eight are accused of conspiracy to murder and preparing to commit an act of terrorism. Prosecutors say the plot involved smuggling liquid components of explosives aboard aircraft.

Hussain's lawyer, Timur Rustem, said he was surprised by the decision to charge his client for failing to disclose information about the alleged plot.

"I personally think this has been done not for a legal reason but for a tactical reason," Rustem said.

Hussain and Mehran Hussain, 24, who was charged earlier, are both accused of withholding information regarding Nabeel Hussain, 22, who is believed to be in custody but so far has not been charged with any offense. News reports say the three men are brothers.

Earlier this week, eight people appeared in court charged with conspiracy to murder and preparing to commit acts of terrorism. Three others — including the mother of an 8-month-old baby — were charged with lesser offenses, including failing to disclose information.

On Wednesday, British police were given another week to interrogate eight remaining suspects. Detectives can seek a judge's permission to hold suspects for up to 28 days before they must be charged or released.

Five people have been released since the alleged plot was revealed and the arrests made two weeks ago.

All of the suspects were arrested in a series of raids in London, Birmingham and suburban High Wycombe on Aug. 10.

Britain's charity regulator on Thursday froze the bank accounts of an aid organization while it investigated alleged links to the foiled plot.

The Charity Commission said it had launched a formal inquiry into Crescent Relief, which raised funds for victims of last year's Pakistan earthquake.

British media have reported that Crescent Relief was founded in 2000 by Abdul Rauf, whose son Rashid Rauf is being held in Pakistan over his alleged key role in the jetliner plot. Media reports have suggested that funds from the charity may have been used to support the planned attacks.

Rashid Rauf's brother, Tayib Rauf, was also arrested but was released Wednesday without charge.

The Charity Commission said the group's funds had been frozen "as a temporary and protective measure."

"We are working with law enforcement agencies to get to the bottom of allegations of possible terrorist abuse of Crescent Relief funds," said Kenneth Dibble, the commission's director of legal and charity services. "The allegations made are very serious, and we are taking this action to protect the charity's funds while the investigation is under way."

No one answered the telephone at Crescent Relief's London offices on Thursday.

After news of the alleged plot broke, Pakistan identified Rashid Rauf as a "key person" in the investigation. A senior government official, who spoke on condition of anonymity because of the case's sensitivity, described him as a "transmitter of messages" between an unnamed Al Qaeda mastermind in Afghanistan and plotters in London.

British authorities have not said whether they believe al-Qaida was involved in the plot, and the Home Office declined to say on Thursday whether it had requested Rashid Rauf's extradition from Pakistan.

In an unusual move earlier this week, senior officers revealed details of their investigation, saying detectives had recovered thousands of pieces of evidence in searches of dozens of properties and two stretches of woodland.

British police seldom disclose evidence about ongoing investigations for fear of prejudicing any future trials.

Investigators have found bombing-making chemicals, including hydrogen peroxide and electrical components during their searches, said Peter Clarke, the head of Scotland Yard's anti-terrorist department.

Months of surveillance had produced "significant video and audio recordings" about the alleged plot, he said Monday, including "martyrdom videos" by some of the prospective bombers.

More than 8,000 items of data storage, such as compact discs, DVDs and memory sticks, were found. A map of Afghanistan, suicide notes and books on explosives were also seized, officials said.