(CNN) -- Investigators are leaning in the direction that the same person or persons who crafted the Christmas Day underwear bomb were behind the PETN-based devices hidden in packages sent from Yemen, a U.S. government official told CNN.
"The thinking is it's the same person or group of people that built the underwear bomb because of the way it's put together," said the official, who had been briefed by multiple U.S. authorities and law enforcement sources. "But this one is about four times as powerful".
American authorities are now endorsing British Prime Minister David Cameron's position that the explosives were designed to take down an airplane, the official said.
One package was found in Dubai in the United Arab Emirates. The other was discovered at an airport in England.
On Friday, U.S. officials said they had not taken a position on whether planes or two Chicago, Illinois, synagogues were the ultimate targets. The packages had the synagogue addresses.
Meanwhile, a woman believed to be connected to a plot to send explosive packages bound for the United States has been arrested in the Yemeni capital of Sanaa, according to a Yemeni government official and a reporter with the state news agency.
CNN
