Abdul Khalek was heading for an office in the capital's Agargaon where he was to sit for an exam for a government job at 11:00am yesterday, but he could not sit for the test as police asked him to go back after stopping him at a checkpoint in Aminbazar.

He was heading towards the capital from Nabinagar in Savar on a bus, Khalek was questioned for around five minutes after he reached Aminbazar around 9:30am.

"Don't you see that we are not allowing any vehicle or transport with passengers to enter [the city]. You better go back home and prepare for your next exam," Khalek quoted a member of police as saying at the checkpoint.

This was just one of many instances of law enforcers making people get down from vehicles, interrogating them, checking their phones and detaining some at checkpoints set up at city entry points at Savar, Gabtoli, Abdullahpur and Tongi since early yesterday morning.

Many of those who were stopped, searched and interrogated had said the police did it to deter people from joining BNP's rally in the capital. But police said they set up the checkpoints to ensure security.

Law enforcers detained at least 35 people -- 23 at Aminbazar and 12 at Abdullahpur -- who were entering the capital yesterday.

These correspondents visited checkpoints in Gabtoli, Aminbazar and Abdullahpur and saw police stopping and searching vehicles since before dawn yesterday.

They made people get down from buses, CNG-run auto-rickshaws, motorcycles, human hauliers, and interrogated them. They also checked their bags and luggage.

During questioning, police forcibly took away mobile phones from some people and went through their photo galleries, Facebook, Messenger and WhatsApp.

After checking, police allowed some to go to their destinations. They had to walk for miles due to the absence of any vehicles, said a number of people who had the experience.

Abdullah Al Kafi, additional superintendent of police in Dhaka, said they detained some people for questioning as their behaviour was suspicious.

Action will be taken against them if anything unlawful is found during interrogation, otherwise they will be released, he added.

Asked about checking phones of people, he said that there was a time when they did body searches, but now the type of crimes have become different, and many crimes are planned on virtual platforms. That is why police check phones.

In the morning, hundreds of people were seen entering Dhaka on foot by crossing the Aminbazar bridge.

"I spent Tk 290 to buy a bus ticket to reach Motijheel, but I was forced to get off midway," said Robiul Islam.

Another man, Riad, alleged that police stopped him at Aminbazar checkpoint around 10:30am when he was going to a friend's home in Khilgaon.

Riad, who was coming from Savar, was questioned for around 15 minutes about where he had come from, where he was going and whether he had any political affiliation.

"At one point, when I got nervous, two policemen even asked me to admit that I am a BNP activist and assured me that they would let me go if I did," said Riad. He said police eventually let him go but not towards Dhaka.

While talking to this newspaper, Mijanur Rahman, one of the detainees, asked, "What did I do wrong by supporting a political party?"

"I vote as a citizen … I pay tax, so, why do they detain me like that," he said as police officials took him away in a police van.

Another detainee, Rajib Hossain, who was picked up from Abdullahpur, said he introduced himself as the joint secretary of Noakhali district unit Chhatra Dal.

"I came to join the BNP rally in Dhaka. But they stopped me at the checkpoint, asked where I came from, where I was going, and forcibly took my phone from my pocket and went through the device.

"At one point, when I said that I came to Dhaka to join the rally, they detained me," he added.