The development comes after intelligence inputs warned of Jaish-e-Mohammed terrorists, which was considered in the A category.
The intelligence inputs suggested that three to four highly motivated and armed terrorists may have infiltrated into the city.
Terrorist could belong to JeM and could have come to Delhi for the execution of any attack, as per the inputs.
Raids started late night yesterday and were conducted in Seelampur, North East, Jamia Nagar and Paharganj area.
Security agencies have been briefed about the situation and are on continuous alert.
As per sources, the terror plot which is being developed by ISI, could include a suicide attack.
In a recent meeting called by active terrorists in Jammu and Kashmir, Jaish Commander in Kashmir Abu Usman had told his accomplices that major blasts will occur in Jammu and Delhi and our members have reached there.
The development comes days after the Indian Air Force bases were under threat of suicide attack by Jaish terrorists. Airbases in and around Jammu and Kashmir, and Punjab were earlier put on alert after the intel warning.