"One person has been held. Two crude bombs were recovered from him," said a police official.
Police received a call at around 6 pm that three men were found loitering around the accused's house in Ravidas slum cluster in south Delhi's RK Puram area and had threatened to blow it up.
"When the residents asked what they were doing there, they said they had come to blow up the house of Ram Singh," said the official.
"While one was overpowered by the crowd, two managed to escape," the official said, adding he was being questioned.
Ram Singh was the driver of the bus on which a 23-year-old medical student was brutally tortured and raped. She died in a Singapore hospital on Saturday.