last updated 8:25 p.m. ET
U.S. officials are investigating a Somali man's alleged attempt to board a flight last month carrying chemicals, liquid and a syringe in a case bearing chilling echoes of the plot to blow up a Detroit-bound airliner on Christmas Day.
Terrorism analysts said the arrest in Mogadishu, the Somali capital, could prove highly valuable for the Detroit investigation if the incidents turn out to be linked. But CBS News correspondent Bob Orr said that the two incidents had major differences.
"For example, the Somali suspect was carrying large quantities of chemicals - more than a pound of ammonium nitrate, half a liter of sulfuric acid - and that was too much to hide on his body," Orr said.
The Somali was arrested by African Union peacekeeping troops Nov. 13 before boarding the Daallo Airlines plane bound for the northern Somali city of Hargeisa, then Djibouti and Dubai.
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"We don't know whether he's linked with al Qaeda or other foreign organizations, but his actions were the acts of a terrorist. We caught him red-handed," said a Somali police spokesman, Abdulahi Hassan Barise.
A Nairobi-based diplomat said the incident has similarities to the attempted attack on Northwest Airlines Flight 253 in that the Somali was said to have a syringe, liquid and powdered chemicals - tools similar to those used by the Nigerian suspect on the Detroit-bound plane. The diplomat spoke on condition he not be identified because he wasn't authorized to release the information.
Barigye Bahoku, the spokesman for the African Union military force in Mogadishu, said the materials could have caused an explosion that would have resulted in cabin decompression, though he didn't think it would have brought the plane down.
For the Amsterdam-to-Detroit flight, Umar Farouk Abdulmutallab allegedly hid explosive PETN in a condom or condom-like bag just below his torso. In the Somali case, the powdered material smelled strongly of ammonia, and samples were sent to London for testing, Bahoku said.
The case drew little attention before the Christmas incident, but on Wednesday U.S. officials began to investigate any possible links to the Detroit attack. None would speak on the record.
In Washington, State Department spokesman Ian Kelly said U.S. investigators are working with Somali authorities, and linking the case to the Christmas attack "would be speculative at this point."
Thomas Sanderson, a security analyst at the Center for Strategic and International Studies, said the Somali suspect is extremely valuable for U.S. investigators, who will compare his statements with Abdulmutallab's.
Police spokesman Barise said the suspect is in Somali custody, but Sanderson said he was sure the U.S. has told the Somali government: "He's ours, and we're taking him."
He said there was no certainty the two were trained by the same group, but believed the similarities are "probably an indicator that more than just two people have been trained and prepared and ordered or convinced to carry out individual acts of terrorism," Sanderson said.
Michael Stock is president of Bancroft, an organization that advises AMISOM, the African Union peacekeeping force in Mogadishu. He said that when the passenger aroused suspicions, Somalis summoned Bancroft guards who patrol the airport.
"At the time, we provided the explosive material itself for analysis and a description of the incident to Western embassy officials involved in supporting AMISOM, for them to pass to law enforcement," Stock said. He said he heard nothing further.
U.S. investigators say Abdulmutallab, the Nigerian suspect held in the Detroit case, told them he received training and instructions from al Qaeda operatives in Yemen, which Western officials say is a jumping-off point for foreign fighters slipping into Somalia. Large swaths of Somalia are controlled by an al Qaeda-linked insurgent group, al-Shabab.
Abdulmutallab is charged with trying to destroy an aircraft. U.S. authorities allege he tried to ignite a two-part concoction of PETN and possibly a glycol-based liquid explosive, setting off popping, smoke and some fire but no deadly detonation.
If the Somali suspect was planning anything similar, it wasn't known what his specific target might have been. Most passengers on Daallo's Mogadishu route are Somali. The carrier's Web site calls it the national airline of Somalia's neighbor, Djibouti. Some 1,800 U.S. troops are stationed in Djibouti, while Dubai would offer the greatest range of Westbound flights along the route in question.
More coverage from CBSNews.com:
Abdulmutallab's Missing Months in Yemen
U.S. Intel Lapses Helped Abdulmutallab
Obama: "Systemic Failure" Allowed Attack
TSA Still Vexed by Explosives Screening
Did Abdulmutallab Talk to Radical Cleric?
Growing Al Qaeda Threat from Yemen
Abdulmutallab Lonely, Web Postings Suggest
Confusion Reigns Over Flight Security
Christmas Incident Renews Scanner Debate
Abdulmutallab's "Jihad Fantasies" Revealed
Behind the Abdulmutallab Security Breach
What Lies Ahead for Air Travel
Al Qaeda: We Planned Flight 253 Bombing
Obama: Plane Bomb Plot a "Serious Reminder"
Expert: New Security Steps a Smokescreen
A Somali security official involved in the Mogadishu arrest said the suspect had a 1-kilogram (2.2-pound) package of chemical powder and a container of liquid chemicals. He said the suspect was the last passenger in line to board.
The man's name was not released, but the security official gave it as Abdi Hassan Abdi and said he was middle-aged. Stock said the name he got was Abdi Hassan Abdullah, but it was unclear that is his real name.
Once the chemicals and syringe were detected, the suspect tried to bribe the team that detained him, the security official said. He said he had a white shampoo bottle containing a black acid-like substance, a clear plastic bag with a light green chalky substance, and a syringe containing a green liquid. The official spoke on condition of anonymity because he wasn't authorized to release the information.
A spokeswoman for Daallo Airlines said that company officials were unaware of the incident and would have to seek more information before commenting. Daallo Airlines is based in Dubai and has offices in Djibouti and France.
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