Terrified of the marauding Pakistan army and its local collaborators, they fled their homes and took shelter at Jharuarbeel, a wetland in Rangpur's Badarganj upazila.
Men, women and children from a dozen villages still could not save themselves from the cold-blooded savagery on the summer noon of April 17, 1971.
Having burned down villages, the troops and armed members of local Jamaat-e-Islami and Islami Chhatra Sangha came charging towards Jharuarbeel.
They surrounded the villagers crouching in the swamp bushes and unleashed a bloodbath. Within five hours, they killed some 1,200 innocent people.
The man who planned it all is ATM Azharul Islam. Commander of notorious Al-Badr force and president of Chhatra Sangha in Rangpur, he himself took part in the massacre.
Azhar and his men also picked up more than 200 Hindu people and students from the area and killed them taking to an unknown place.
For the killing of those 1,400 civilians, Azhar was awarded death sentence by the International Crimes Tribunal-1 yesterday. Of all the massacres over which the tribunal has conducted trials so far, this was the largest.
He was sentenced to death on two other charges as well -- a mass killing in Dhappara of Badarganj on April 16 and an act of genocide that claimed the lives of four Hindu teachers of Rangpur Carmichael College and the wife of one of them.
"All the crimes, particularly relating to genocide, murder of numerous unarmed innocent civilians and other inhumane acts as crimes against humanity were worst and barbarous types of crimes and are particularly shocking to the conscience of mankind," said Justice M Enayetur Rahim, chairman of Tribunal-1, while reading out the verdict.
He also said it was well proved that the accused had "direct complicity and substantially contributed and facilitated in the commission of such barbarous types of crimes".
"... no punishment other than death will be equal to the said horrendous crimes for which the accused has been found guilty beyond reasonable doubt in the above mentioned three charges," said the judge in a packed courtroom.
Azhar, now assistant secretary general of Jamaat-e-Islami, was also sentenced to jail on two other charges.
The 62-year-old has to serve 25 years' rigorous imprisonment for his complicity in the rape of a pregnant woman at Rangpur Town Hall and five years for involvement in torturing a freedom fighter and his brother at an Al-Badr camp in the town.
All the sentences will merge into a single sentence of death, said the court.
The tribunal, however, acquitted him of another charge relating to the killing of 10 people in Rangpur town as the prosecution could not prove it.
The prosecution also failed to prove his "superior status" over the Pakistan army.
As a leader of Jamaat's student body Islami Chhatra Sangha during the war, the accused played a significant role in the atrocities and aided the Pakistani occupation troops in committing horrific crimes. But, the court said, these are not enough to hold him liable on superior command responsibility.
Azhar, a resident of Badarganj upazila, was brought to the court around 9:00am yesterday in a prison van. He was produced at the courtroom at 10:58am.
Wearing a biscuit-coloured punjabi, white pyjama and a sweater, he sat in silence in the dock until the court read out the punishment part of the verdict.
"It's a dictated verdict... dictated ... I'm completely innocent," he shouted, standing up. Someone in the courtroom also shouted “Shut up!”
However, police sat him down.
As Justice Enayetur Rahim along with two members of the tribunal Justice Jahangir Hossain and Justice Anwarul Haque left the courtroom at 12:45pm, Azhar said, "... Allah will try you, Insha'Allah."
In reply to the defence argument that their client was being tried on political grounds, the court said the trial was for the offences committed in 1971.
"Present status and position of the accused is not same and similar to 1971,” Justice Jahangir Hossain said while reading out the observations.
“We have already observed that in 1971 accused ATM Azharul Islam was a potential leader of ICS [Islami Chhatra Sangha] and also a leader of Al-Badr Bahini, a 'death squad', of Rangpur district.
"Thus we have no hesitation to hold that instant trial of the accused is not being held for political purpose."
Referring to Azhar's crimes, the tribunal said, "We've taken due notice of the intrinsic magnitude of the offences of genocide and crimes against humanity which are predominantly shocking to the conscience of mankind."
Besides, it said, the accused never expressed repentance for his conducts and it didn't find any mitigating factors to award lesser sentence to the accused other than death.
Expressing satisfaction, the prosecution said the verdict has fulfilled the expectations of victims' families and the nation as well.
"The verdict would help the country go another step towards establishing rule of law and ending the culture of impunity," prosecutor Zead Al Malum told reporters.
Different pro-liberation organisations hailed the verdict and demanded its immediate execution.
The defence said they would challenge the verdict at the Supreme Court. "We will go to the Supreme Court and hope to get justice there," said defence lawyer Tajul Islam.
“Justice would have been done if the tribunal had thrown the [prosecution] evidence into the dustbin,” he said.
Rather, the lawyer added, justice would have been served if the prosecution was fined for coming up with such evidence.
Protesting the verdict, Jamaat-e-Islami has called countrywide dawn-to-dusk hartal for today and tomorrow.
According to the law, a war crimes convict can file appeal with the Appellate Division of the Supreme Court within 30 days from the date of pronouncement of the verdict.
The Jamaat leader was arrested from the capital on August 23, 2012 in the case. He was indicted on six charges on November 12 last year.
After proceedings for 10 months, the tribunal on September 18 this year kept the case on CAV (Curia Advisari Vult, a Latin legal term meaning verdict would be delivered anytime).
A total of 19 people, including the investigation officer, testified as prosecution witnesses while the defence produced a single witness in the case.
With Azhar, eight top Jamaat leaders have already been handed down punishment for committing war crimes during the ninth-month war in 1971.