A German and a Turkish citizen have been arrested on suspicion of collaborating with a terrorist group whose plans for attacks on U.S. targets in Germany were foiled last year, authorities said Friday.

Federal prosecutors said in a statement that the pair, both 27 years old, were arrested Thursday in the Frankfurt area on suspicion of links to Islamic Jihad Union, an offshoot of the Islamic Movement of Uzbekistan, a jihadist group with ties to Al Qaeda.

Prosecutors identified the two as Omid S., a German citizen of Afghan descent who is suspected of membership in a terror organization, and Hueseyin O., a Turkish citizen suspected of supporting a terror organization. Both are suspected of involvement with the Islamic Jihad Union's German cell.

According to the U.S. State Department, the Islamic Jihad Union was responsible for coordinated bombings outside the U.S. and Israeli embassies in the Uzbek capital, Tashkent, in July 2004.

Members have been trained by Al Qaeda instructors to use explosives and the group has ties to Usama bin Laden and fugitive Taliban leader Mullah Omar, the State Department says.

Prosecutors said they believe both suspects were aware of the German cell's plot to target U.S. and German interests — a plot thwarted by authorities in September 2007. Three suspected members of the cell were arrested then and charged earlier this month.

During that arrest, prosecutors said they confiscated a mobile phone that contained information on both Omid S.' and Hueseyin O.'s bank accounts that led them to the pair.

They said Omid. S. had "traveled to an Islamic Jihad Union training camp near the Pakistan-Afghanistan border in the spring and summer of 2007, where he completed a course." He is also suspected of purchasing equipment for the Islamic Jihad Union and bringing it to the group in Pakistan.

Hueseyin O. also traveled to Pakistan but was prevented by authorities there from reaching the camp, prosecutors said, saying that before he left, he gave his debit card and PIN number to Adem Yilmaz, one of the suspected members of the German cell arrested in 2007.

Along with Fritz Martin Gelowicz, and Daniel Martin Schneider, Yilmaz has been charged with membership in a terrorist organization and plotting a terror attack for his role in stockpiling 1,600 pounds of highly concentrated hydrogen peroxide to build bombs.

Authorities said the chemicals were enough to build bombs more powerful than those that killed 191 commuters in Madrid in 2004 and 52 people in London in 2005.

Hueseyin O. and Omid S. were being held in detention on Friday pending the results of a criminal investigation. The names of their lawyers were not immediately available.