German police said they detained two men at Berlin's Tegel airport on Wednesday after a woman who overheard their conversation in Russian at a ticket counter got the impression they were planning to hijack a plane to Moscow.
The woman alerted police, who detained the men, aged 49 and 26. German investigators were questioning them.
"Two men have been detained after one other passenger got the impression they were planning to hijack an Air Berlin flight to Moscow," a police spokesman said. "The plane was evacuated and is being examined. The other passengers were questioned."
An airport official said it looked like there might have been a false alarm.
The Air Berlin flight was evacuated and 132 passengers were put on another flight to Moscow, police said. The witness overheard the conversation at around 12:40 pm (1040 GMT).