Police cars stand at the entrance of an underground parking lot in Berlin Monday Jan. 14, 2013. German police say a 30-meter (100-foot) tunnel dug by robbers who raided a Berlin bank was "very professional" and must have taken weeks or even months to complete. Berlin police spokesman Thomas Neuendorf says the tunnel led from the underground garage beneath a green space into the bank's safe deposit room. Neuendorf told The Associated Press on Monday that the tunnel was elaborately constructed and even had ceiling supports to stop it collapsing. Police are still trying to determine what valuables were stolen from the deposit boxes. AP Photo/dapd/ Tobias Koch Customers and a camera man stand in front of a Berlin bank Monday Jan. 14, 2013. German police say a 30-meter (100-foot) tunnel dug by robbers who raided the Berlin bank was "very professional" and must have taken weeks or even months to complete. Berlin police spokesman Thomas Neuendorf says the tunnel led from an underground garage beneath a green space into the bank's safe deposit room. BERLIN (AP) - German police say robbers dug a 30-meter (100-foot) tunnel into the safe deposit room of a Berlin bank and escaped with their haul, setting a fire as they left to cover their tracks. Berlin police spokesman Thomas Neuendorf says the tunnel led from an underground garage into the bank's safe deposit room. Neuendorf told The Associated Press Monday that the tunnel was "very professional" and must have taken weeks or even months to complete. It was elaborately constructed and even had ceiling supports. Police were alerted to the break-in early Monday when a security guard noticed smoke coming from the deposit room. Neuendorf says police are still trying to determine what valuables were stolen from the deposit boxes. Details of the heist called to mind the spectacular robbery of another Berlin bank in 1995. During that robbery thieves entered the bank through the door, took a hostage and demanded a helicopter and ransom. Police besieged and eventually stormed the safe room where the thieves had holed up only to find out they had escaped through a tunnel dug by accomplices. Several - but not all - of the thieves were later caught.