German police say they have received dozens of tips after releasing images of the 45-meter (150-foot) tunnel dug by robbers into the safe deposit room of a Berlin bank last weekend.
Police also issued an artist's sketch of a stocky man in his 30s or 40s considered a possible suspect in the audacious heist.
Spokeswoman Diana Born said Friday that a special task force is sifting through 90 tips received over the past days.
Photographs show circular holes in the huge concrete wall of an underground parking garage where the robbers are believed to have begun their work last February.
Behind the wall the tunnel can be seen, supported by neat pillars to prevent it from collapsing.
Police still don't know what was stolen or how much it was worth.