Activists of the Hindu fundamentalist organisation Bajrang Dal attacked the Pakistan International Airlines (PIA) office in New Delhi, India media reported.
PIA officials have confirmed the attack, saying that activists of Hindu hardline group vandalized the office and raised anti-Pakistan slogans.
Sources said the attackers threatened the PIA staff present in the office.
PIA office is located at the centre of Delhi.
The PIA spokesman said staff of the national airline remained unhurt in the attack.
Pakistan has strongly condemned the attack and asked Indian authorities to enhance the security of the staff.