In the world of forensic phsycology, it is said that many a times during Serial Killing Investigations, the Serial Killer himself comes to the law and offers help. (the real motive however is to get rid of any clues he/she may have left at the crime scene) The main assumption is that NO MATTER WHAT THE CULPRITS ALWAYS LEAVE SOMETHING ON THE CRIME SCENE, CELLPHONE, A PURSE, KEYS, FINGERPRINTS and other evidence.
If i was incharge of Jaipur Blast investigations I would take this US help offer with a grain of salt and tell em no thank you. this is creepy indeed