Pakistan ? Indian aircraft violated Pakistan’s airspace Saturday but were chased back over the border by Pakistani fighter jets, an Air Force spokesman here said.

The alleged incident comes amid heightened tensions between the nuclear-armed rivals over last month’s deadly attack in Mumbai. India has said the attack, which left more than 170 people dead, had roots in Pakistan.

Pakistan Air Commodore Himayun Viqar said the Indian aircraft crossed over the border some one to three miles (two to four kilometers) in Pakistan-controlled Kashmir and over the eastern city of Lahore.