Yemen condemned Tuesday the failed attempt claimed by Al-Qaeda to blow up a US airliner on Christmas Day - after confirming the attacker had been in the Gulf country until earlier this month, DPA reported.
The suspect in the plot, Umar Farouk Abdulmutallab, had left Yemen earlier in December after attending Arabic language classes there since early August, the country's foreign ministry confirmed.
"Yemen condemns such terrorist acts targeting the innocent and it reiterates its full support for the fight against terror anywhere on the globe," the official SABA news agency quoted a foreign ministry official as saying.
The University of Wollongong in Dubai, meanwhile said Tuesday that the 23-year-old Nigerian man had attended classes there from January until June.
"He has not come to my attention for any reason whatsoever other than now," Raymi van der Spek, Vice-President of Administration at the school told Gulf News.
IntelCenter, a private firm the monitors terrorist activity, said al-Qaeda in the Arabian Peninsula, or AQAP, took responsibility for the failed plot to blow up Delta/Northwest Airlines Flight 253 on Friday.
The group warned of more attacks against Americans.
"We will strike you with what you have no previous knowledge of, for as you kill you shall be killed, our vengeance is near," the statement said.
Abdulmutallab is believed to have received training and the explosives from al-Qaeda in Yemen.
Yemeni security authorities said they were tracing his contacts in the Gulf, and will give the investigation results to the US anti-terrorism agencies.
As Sanaa struggles to control the country, Yemen has been a growing source of concern for US officials as it appears al-Qaeda has gained a foothold there over the past decade and set up bases in the south.
Washington has stepped up its aid to the government and cooperation has increased in the fight against al-Qaeda in the poor Gulf country.
Airstrikes in the south of Yemen in the last two weeks have killed over 60 people. The government says they were militants, but regional officials in the affected areas reported civilian casualties as well.
Some 29 Islamist militants have also been arrested this month, the Defense Ministry in Sanaa said.