German police found traces of explosives after searching a flat in the eastern town of Chemnitz on Saturday, adding that a suspect has fled the scene, a spokesman for criminal investigators said.
Security sources told dpa there was a possible Islamist background to the discovery.
"Suspicions of plans for a bomb attack" had led police to raid an apartment and place a high-rise apartment block on lockdown earlier Saturday, a police spokeswoman in the regional headquarters in Dresden said.
Local police were informed about a "serious threat" by the German intelligence service on Friday night, regional police spokesman Tom Bernhardt said.
Police are still searching for suspects after the raid, which did not lead to any arrests.
Germany has been on high alert since two terrorist attacks occurred over the course of one week in July. Both were claimed by Islamic State militants and carried out by asylum seekers.