Bangladesh has accused Pakistan of interfering in its internal affairs by criticizing the execution of two opposition leaders for alleged war crimes during the country's 1971 war of independence from Pakistan.

Bangladesh Junior Foreign Affairs Minister Shahriar Alam said a "strongly worded protest note" was handed to Pakistan's envoy on Monday saying the criticism was unacceptable.

Pakistan's Foreign Ministry earlier said the men's trials were flawed and that it was "deeply disturbed" by their executions on Sunday.

Bangladesh was on high alert Monday against any violence in response to the hangings, with thousands of security personnel patrolling the cities. There has been international concern about the legal process that led to the executions.

Bangladesh was the eastern part of Pakistan until the 1971 war in which it became independent.