Sept. 3, 2010: UPS cargo plane crashes at an air force base shortly after take-off from Dubai airport, killing two crewmembers on board. Reports said a fire had broken out in the plane just after it took off from Dubai international airport.
Sept. 4, 2010: Yemen announces the arrest of a top AQAP leader, ex-Gitmo detainee Jaber al-Fayfi.
Sept. 21, 2010: AQAP kidnap senior Yemeni security officer in Saada, and request the release of Fayfi in exchange for the Yemeni officer.
(On Oct. 15, Saudi authorities announced that Fayfi has turned himself in to Saudi authorities, was repatriated to Riyadh from Yemen.)
Sept. 2010: U.S. intelligence officials are warned by the Saudis that terrorists were planning to mail chemical and biological materials, as part of an attack on America and other Western countries using the mail.
Sept 23, 2010: The alert was published in a bulletin from the Homeland Security Department
Oct. 28, 2010: Leicestershire police called to East Midlands airport at 3:28 a.m. BST to check out a suspicious package that was shipped aboard UPS plane.
The parcel was a printer containing an ink cartridge with protruding wires, a circuit board and partly covered in a white powder. The parcel turned out to contain explosives.
U.K. inform counter-terrorism officials in the U.S. At 10:35 p.m. EST time, President Obama was informed of the find.
Oct. 29, 2010: News emerges about four UPS planes quarantined and searched for suspicious packages in the U.S., and other suspicious packages being checked out in the U.K. and France.
NYPD seize a UPS truck known to have a package from Yemen on board. Truck was later cleared.
Report says anti-terror authorities in the U.S. and the U.K. examining suspected explosive packages addressed to Chicago-area synagogues and packed aboard cargo jets.
Pictures released of the suspect package intercepted in the U.K., show a printer's ink cartridge containing white powder and a mobile phone circuit board. The white substance is confirmed to be PETN.
Second suspect package sent from the same source in Yemen via FedEx, discovered at FedEx warehouse at Dubai airport. Turned out to be identical to that intercepted in the U.K.
President Obama makes a TV address, says that both packages did contain explosives -- that they were essentially bombs -- and that they represented a "credible terrorist threat against our country".
John Brennan, the President's assistant for homeland security and counter-terrorism says the U.S. was acting on specific intelligence that had identified a parcel shipped on a UPS flight via the East Midlands
Oct. 30, 2010: Dubai police issues a statement confirming suspect parcel was a bomb that contained PETN and lead azide PbN6, an explosive generally used in detonators.
"The investigation into the suspicious packages that came from Yemen has shown that (one of them included) a computer printer whose ink contained explosive material. The device was prepared in a professional manner and equipped with an electrical circuit linked to a mobile telephone (SIM) card concealed in the printer. The manner in which this device was prepared bears the hallmarks of those used by terrorist organizations like al Qaeda."
Dubai Police release pictures showing an HP printer, an electric circuit board fitted to printer. (Dubai Police pictures downloaded from the Emirates News Agency Website)
U.S. Homeland Security Secretary Janet Napolitano says parcel bombs sent from Yemen bear the hallmarks of AQAP.
Yemeni authorities say that are inspecting a number of suspicious packages, made some arrests in relation to the plot.
U.S. President Barack Obama discusses failed bomb plot in phone calls with Saudi King Abdullah and British Prime Minister David Cameron.
British Home Secretary Theresa May says U.S.-bound package from Yemen was a "viable" bomb that could've brought down an aircraft if it had been triggered.
U.K. forensic experts say one of the two bombs was linked to a mobile phone, the other was attached to a timer, and were designed to explode in mid-air.
More on Terror Packages:
Yemen Arrests Woman for Sending Mail Bombs
U.K. Official: Device Could Have Exploded
U.K. Official: Device Could Have Exploded
Investigators Searching for More Mail Bombs
Security Gaps Plague Cargo Shipping
Explosives Found on Planes Amid U.S. Terror Probe
PETN Explosive a Favorite of Terrorists
More on Yemen and AQAP: