WASHINGTON - U.S. government agencies are on alert for militants trying to attack the United States over the Christmas holidays but are not aware of a specific plot, intelligence and law enforcement officials said.
The Obama administration is edgy about holiday threats after a Nigerian man, Umar Farouk Abdulmutallab, allegedly tried to bring down a Detroit-bound passenger plane on Christmas Day last year with a bomb hidden in his underpants.
The Internet is teeming with threats against Americans and Europeans around this year's busy shopping and travel period, said the officials and a private expert who monitors postings on websites run by al Qaeda and other militant groups.
But officials said U.S. agencies had not pinpointed a plot or suspects planning an attack.
President Barack Obama and many senior officials plan to travel outside Washington over the holidays and threat information flowing into U.S. agencies has not caused them to alter their plans.
"I think it would be the absolutely wrong thing to ... cancel plans," one intelligence official said. "Remember, there is always 'chatter' in the system. Let's not give them an easy win by over-reacting."
Fears of a possible repeat of last year have been heightened by:
-- bombs put aboard U.S.-bound cargo planes this fall;
-- a warning by authorities in Iraq that militants might be headed for Europe or the United States;
-- a failed bombing by an Iraqi-born suspect in a Swedish shopping district this month;
-- a round-up of suspects in Britain earlier this week;
-- the arrest in November of a suspect who allegedly plotted to bomb a Christmas tree lighting in Portland, Oregon.
"BLACK TEARFUL DAYS"
The White House convened a meeting of senior officials from various agencies and departments on Tuesday to "review the latest threat reporting" and coordinate security plans for the holiday period, John Brennan, Obama's chief counter-terrorism advisor, told reporters on Wednesday.
Brennan insisted U.S. precautions have been improved since the underpants bombing attempt and incidents that included the shooting of soldiers at Fort Hood, Texas, allegedly by an Army psychiatrist, and the attempted car bombing of New York City's Times Square by a Pakistan-born militant.
Since last Christmas, a counter-terrorism official said, rules for using intelligence information to screen airline passengers have been tightened.
This means a suspect like Abdulmutallab -- whose name was in a classified intelligence database but not on a "no fly" list -- would be questioned before he boarded his U.S.-bound flight, the official said.
Evan Kohlmann, a private expert who monitors militant traffic on the Internet, said websites affiliated with al Qaeda in the Arabian Peninsula, the Yemen-based group suspected of equipping Abdulmutallab with his underpants bomb, have been quiet in this year's pre-Christmas period.
But other websites, including some maintained by militants believed to be living in the United States, have been blaring threats.
"Black Tearful Days -- Coming Soon for The Europeans and The Americans. Omar Faruk (Abdulmutallab) was The Beginning," said a headline on a site that Kohlmann said is operated by the Somalia-based group Shabaab al-Mujahideen.
Last week, the FBI and Department of Homeland Security issued a bulletin to law enforcement agencies advising extra vigilance during the holiday period.
"We've seen in the past terrorists using the holidays as a jumping-off point," said a senior official familiar with the bulletin.
U.S. and European counter-terrorism officials said they are most worried about isolated, "lone wolf" militants who would not have come to the attention of a law enforcement or intelligence agency.
Officials said they hope -- and believe -- they have a fairly good handle on the activities of better organized groups and cells. (Editing by John O'Callaghan)
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