Three people have been arrested in Austria in connection with a video posted on a website threatening attacks on Germany and Austria, officials say.
The video was made by Islamic militants and published in March, Austrian broadcaster ORF reported.
The country's Interior Ministry said the detained militants were suspected al-Qaeda sympathisers.
They had threatened to attack Austria and Germany unless both withdrew troops from Afghanistan, the ministry said.
Austrian Interior Minister Guenther Platter was due to hold a news conference at 1600 (1400GMT).
The announcement came two days after a telephone bomb threat triggered an alert at a US air base at Spangdahlem, Germany.
Last week, German police arrested three people they said had been planning a series of car bombings on targets there, including US military bases and nightclubs frequented by American citizens.