Two American-Yemeni men who flew from Chicago to Amsterdam and were detained on Monday in the Netherlands on suspicion of being on a dry run for a future terror attack, reportedly do not appear to be involved in any conspiracy and did not know each other before being arrested.

According to two U.S. law enforcement officials, suspicions that they were involved in an attempt to test the security of the aviation system with fake bombs appeared misplaced. On the contrary, they said, the two became the focus of an international terrorism scare as a result of a series of odd events.

"It doesn't look like a conspiracy, or a test run and these guys don't show up on any of our lists," The Washington Post quoted one of the law enforcement officials, as saying.

On Sunday, airport security screeners in Birmingham recovered 7,000 dollars in cash, a cellphone taped to a bottle of Pepto-Bismol, three cellphones taped together and several watches taped together from one of the men.

Since no evidence of explosives was found, the 48-year-old man was permitted to fly to O'Hare Airport in Chicago. He was joined there by the second man, and they both boarded United Airlines Flight 908 to Amsterdam.

However, the officials discovered that at Birmingham, the 48-year-old passenger had checked his luggage on a different set of flights, to Dulles International Airport outside Washington and on to Sana, Yemen, by way of Dubai.

After security agents realized that he had not boarded the flight from Chicago to Dulles, they ordered the airliner back to the gate and retrieved his luggage, which contained the suspicious items.

The duo were detained by the police when they arrived at Schiphol Airport at the request of the American authorities "on the basis of suspicions of preparation for terrorist attacks." A probe is being carried out by the Federal Bureau of Investigation (FBI) to tackle the matter. (ANI)