The two missing Indian clerics are believed to be in the custody of Pakistan Intelligence Agency (PIA), according to official sources on Saturday.

"Two missing Indian clerics of Delhi's Hazrat Nizamuddin Dargah are in custody of Pakistan's intelligence agencies," an official was quoted as saying by a news agency.

Expressing deep concern over the case, External Affairs Minister Sushma Swaraj on Friday had said that she has spoken to the Pakistani authorities about the matter.

The Pakistan Foreign Office had on Friday also said that they have taken the matter of tracing the two Indian Sufi clerics who went missing in Pakistan since Wednesday.

Foreign Office spokesperson Nafees Zakaria had confirmed the request which had been received and forwarded to the Interior Ministry, who are pursuing the matter.

The two Indian nationals identified as Syed Asif li Nizami and his nephew Nazim Ali Nizami, who went to Pakistan on March 17, were reported missing after they landed at Karachi airport.

Syed Asif Ali Nizami is the head priest (Sajjadanashin) of Hazrat Nizammuddin Aulia dargah. The two priests had gone to Pakistan as part of exchanges between Hazrat Nizamuddin dargah in India and Data Darbar in Lahore.