An anonymous threat call to carry out blasts in at least half a dozen locations was received by the Mumbai police control around 7.30 a.m. Wednesday. The caller threatened to blow up around half a dozen targets -- which he did not specify -- just after noon today, officials said. The railway and security authorities at CST were alerted and the entire station complex -- a World Heritage Building -- shifted to a high security gear. Confirming the developments, an official spokesperson for Central Railways (CR) said: "We are taking all possible precautions, making announcements, deploying the dog squad and sufficient security personnel to ensure there is no untoward incident." He said there was no panic among the three million plus commuters who use the CR services daily. Besides CST, security has been tightened at various locations, including the famed Siddhi Vinayak Temple in Prabhadevi, some five star hotels, Churchgate and Dadar railway stations.