Two officials working with the Indian High Commission in Islamabad have reportedly gone missing, sources told .
The two officials are untraceable for the last few hours.
Recently reported on how Pakistan 's spy agency ISI has been tailing and harassing Indian officials and also increased their presence at the residence of Acting High Commissioner Gaurav Ahluwalia.
This incident came in the backdrop when two Pakist officials were caught red-handed and sent back trying to collect classified information and spying in Delhi.
South block is watching the developments closely, the Indian mission has also launched a complaint with local authorities and taken up the matter Pakistan Foreign Ministry.
This incident can cause a further dip in the already tense India-Pakistan relations.
Earlier in the month, India deported two Pakist officials for espionage activities in India.
( With inputs from ANI )