In a major swoop, more than 20 residences and offices of land developers and realtors were raided by Income Tax (I-T) department sleuths aided by a posse of police in and around Bangalore today."Raids are still on," an I-T department official told PTI.The simultaneous raids were conducted based on credible information, he said on condition of anonymity.Land prices in and around Bangalore have shot up in recent times.The I-T department declined to disclose the names of individuals whose premises are being raided.