Unidentified persons broke into the house of Indian High Commissioner Satyabrata Pal in Islamabad two days ago, prompting New Delhi to lodge a strong protest with the Pakistan government.The break-in occurred during the intervening night of Monday and Tuesday and involvement of some state agencies is suspected.The Ministry of External Affairs summoned Pakistan's Deputy High Commissioner Afrasiab here and lodged a ‘strong protest’, official sources said.A similar protest was lodged in Islamabad by the Indian High Commission.Pakistan has assured that the matter will be looked into.