Delhi Police has arrested 12 persons assumed to be related with a terror outfit preparation an attack in the city and improved explosives from their ownership after a series of overnight raids in the Delhi and neighbouring states.

The raid which is ongoing of a joint operation of Delhi Police and a central intelligence agency.

Although, a team of the force's anti-terror unit Special Cell zeroed in on two of the youths, though they were apparently in the process of making unplanned short-tempered device, from east Delhi's Gokulpuri area, names of the others emerged during their questioning and they were tracked down one after another in the wee hours today, a senior official said.

“All of them are alleged to be associates of a sleeper unit of a terror outfit, preparation an attack in the national capital and other cities”, the official said.

Further added, “Special Cell teams are conducting raids in Delhi and UP, and several arrests are likely in the next 24 hours”.

Senior official added, “The 12 are being asked by Special Cell sleuths and brain officials and investigation is underway”