Germany and Britain were among several Western countries to urge their nationals to leave the eastern Libyan city of Benghazi on Thursday, days after a deadly attack by Islamist militants in neighboring Algeria.

Britain cited a “specific and imminent” threat to Westerners in Libya’s second largest city, but officials declined to give any details.

Spiegel, citing sources in the German Federal Intelligence Service (BND), said on Sunday al Qaeda and other militant Islamist groups were specifically preparing attacks on British and German citizens in the area.

It gave no further details and the BND declined to comment.